diff --git a/DEPS b/DEPS
index 73b47bdb1ac..0d26b689b77 100644
--- a/DEPS
+++ b/DEPS
@@ -262,7 +262,7 @@ allowed_hosts = [
 ]
 
 deps = {
-  'src': 'https://github.com/flutter/buildroot.git' + '@' + '60415e4cb48742a60ba3859d92bbdcb7d14841b0',
+  'src': 'https://github.com/flutter/buildroot.git' + '@' + '6f31be56e1058997feac2e93ff67fef21ae25eaf',
 
    # Fuchsia compatibility
    #
@@ -325,7 +325,7 @@ deps = {
   'src/third_party/protobuf':
    Var('fuchsia_git') + '/third_party/protobuf' + '@' + Var('dart_libprotobuf_rev'),
 
-  'src/build/secondary/third_party/protobuf':
+  'src/flutter/build/secondary/third_party/protobuf':
    Var('fuchsia_git') + '/protobuf-gn' + '@' + Var('dart_protobuf_gn_rev'),
 
   'src/third_party/dart':
diff --git a/engine/src/flutter/.gitignore b/engine/src/flutter/.gitignore
index a19d20d3838..fcd681e7bd9 100644
--- a/engine/src/flutter/.gitignore
+++ b/engine/src/flutter/.gitignore
@@ -130,3 +130,4 @@ app.*.symbols
 
 # Prebuilt binaries.
 /prebuilts/
+/build/secondary/third_party/protobuf
diff --git a/engine/src/flutter/build/secondary/flutter/third_party/glfw/BUILD.gn b/engine/src/flutter/build/secondary/flutter/third_party/glfw/BUILD.gn
new file mode 100644
index 00000000000..98c3fe43e7e
--- /dev/null
+++ b/engine/src/flutter/build/secondary/flutter/third_party/glfw/BUILD.gn
@@ -0,0 +1,125 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import("glfw_args.gni")
+
+_checkout_dir = "//flutter/third_party/glfw"
+
+config("relative_glfw_headers") {
+  include_dirs = [
+    "$_checkout_dir/include",
+    "$_checkout_dir/include/GLFW",
+  ]
+}
+
+source_set("glfw") {
+  public = [
+    "$_checkout_dir/include/GLFW/glfw3.h",
+    "$_checkout_dir/include/GLFW/glfw3native.h",
+  ]
+
+  sources = [
+    "$_checkout_dir/src/context.c",
+    "$_checkout_dir/src/egl_context.c",
+    "$_checkout_dir/src/init.c",
+    "$_checkout_dir/src/input.c",
+    "$_checkout_dir/src/monitor.c",
+    "$_checkout_dir/src/null_init.c",
+    "$_checkout_dir/src/null_joystick.c",
+    "$_checkout_dir/src/null_joystick.h",
+    "$_checkout_dir/src/null_monitor.c",
+    "$_checkout_dir/src/null_platform.h",
+    "$_checkout_dir/src/null_window.c",
+    "$_checkout_dir/src/osmesa_context.c",
+    "$_checkout_dir/src/platform.c",
+    "$_checkout_dir/src/vulkan.c",
+    "$_checkout_dir/src/window.c",
+  ]
+
+  include_dirs = [ "$_checkout_dir/src" ]
+
+  public_configs = [ ":relative_glfw_headers" ]
+
+  if (is_win) {
+    sources += [
+      "$_checkout_dir/src/wgl_context.c",
+      "$_checkout_dir/src/win32_init.c",
+      "$_checkout_dir/src/win32_joystick.c",
+      "$_checkout_dir/src/win32_joystick.h",
+      "$_checkout_dir/src/win32_module.c",
+      "$_checkout_dir/src/win32_monitor.c",
+      "$_checkout_dir/src/win32_platform.h",
+      "$_checkout_dir/src/win32_thread.c",
+      "$_checkout_dir/src/win32_time.c",
+      "$_checkout_dir/src/win32_window.c",
+    ]
+
+    defines = [ "_GLFW_WIN32" ]
+  } else if (is_linux) {
+    sources += [
+      "$_checkout_dir/src/glx_context.c",
+      "$_checkout_dir/src/linux_joystick.c",
+      "$_checkout_dir/src/linux_joystick.h",
+      "$_checkout_dir/src/posix_module.c",
+      "$_checkout_dir/src/posix_poll.c",
+      "$_checkout_dir/src/posix_poll.h",
+      "$_checkout_dir/src/posix_thread.c",
+      "$_checkout_dir/src/posix_thread.h",
+      "$_checkout_dir/src/posix_time.c",
+      "$_checkout_dir/src/posix_time.h",
+      "$_checkout_dir/src/x11_init.c",
+      "$_checkout_dir/src/x11_monitor.c",
+      "$_checkout_dir/src/x11_platform.h",
+      "$_checkout_dir/src/x11_window.c",
+      "$_checkout_dir/src/xkb_unicode.c",
+      "$_checkout_dir/src/xkb_unicode.h",
+    ]
+
+    defines = [
+      "_GLFW_X11",
+      "_GLFW_HAS_XF86VM",
+    ]
+
+    libs = [
+      "X11",
+      "Xcursor",
+      "Xinerama",
+      "Xrandr",
+      "Xxf86vm",
+    ]
+  } else if (is_mac) {
+    sources += [
+      "$_checkout_dir/src/cocoa_init.m",
+      "$_checkout_dir/src/cocoa_joystick.h",
+      "$_checkout_dir/src/cocoa_joystick.m",
+      "$_checkout_dir/src/cocoa_monitor.m",
+      "$_checkout_dir/src/cocoa_platform.h",
+      "$_checkout_dir/src/cocoa_time.c",
+      "$_checkout_dir/src/cocoa_window.m",
+      "$_checkout_dir/src/nsgl_context.m",
+      "$_checkout_dir/src/posix_module.c",
+      "$_checkout_dir/src/posix_thread.c",
+      "$_checkout_dir/src/posix_thread.h",
+    ]
+
+    defines = [ "_GLFW_COCOA" ]
+
+    cflags = [
+      "-Wno-deprecated-declarations",
+      "-Wno-objc-multiple-method-names",
+    ]
+
+    frameworks = [
+      "CoreVideo.framework",
+      "IOKit.framework",
+    ]
+  }
+
+  if (glfw_vulkan_library != "") {
+    defines += [ "_GLFW_VULKAN_LIBRARY=" + glfw_vulkan_library ]
+  }
+
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
+}
diff --git a/engine/src/flutter/build/secondary/flutter/third_party/glfw/README b/engine/src/flutter/build/secondary/flutter/third_party/glfw/README
new file mode 100644
index 00000000000..404ef3cae2e
--- /dev/null
+++ b/engine/src/flutter/build/secondary/flutter/third_party/glfw/README
@@ -0,0 +1,13 @@
+Name: GLFW
+License: zlib/libpng (BSD-like)
+Upstream Git: https://github.com/glfw/glfw
+Version: 3.2.1
+Description:
+
+GLFW is an Open Source, multi-platform library for OpenGL, OpenGL ES and
+Vulkan development on the desktop.
+
+To update:
+- Advance the pinned hash in DEPS, which should map the repository to
+  //third_party/glfw
+- Update BUILD.gn if necessary for changes.
diff --git a/engine/src/flutter/build/secondary/flutter/third_party/glfw/glfw_args.gni b/engine/src/flutter/build/secondary/flutter/third_party/glfw/glfw_args.gni
new file mode 100644
index 00000000000..c5903ad2078
--- /dev/null
+++ b/engine/src/flutter/build/secondary/flutter/third_party/glfw/glfw_args.gni
@@ -0,0 +1,7 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+declare_args() {
+  glfw_vulkan_library = ""
+}
diff --git a/engine/src/flutter/build/secondary/testing/gmock/BUILD.gn b/engine/src/flutter/build/secondary/testing/gmock/BUILD.gn
new file mode 100644
index 00000000000..ecf49f0ff7f
--- /dev/null
+++ b/engine/src/flutter/build/secondary/testing/gmock/BUILD.gn
@@ -0,0 +1,50 @@
+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+config("gmock_config") {
+  # Gmock headers need to be able to find themselves.
+  include_dirs = [ "include" ]
+}
+
+static_library("gmock") {
+  # TODO http://crbug.com/412064 enable this flag all the time.
+  testonly = !is_component_build
+  sources = [
+    # Sources based on files in r173 of gmock.
+    "include/gmock/gmock-actions.h",
+    "include/gmock/gmock-cardinalities.h",
+    "include/gmock/gmock-generated-actions.h",
+    "include/gmock/gmock-generated-function-mockers.h",
+    "include/gmock/gmock-generated-matchers.h",
+    "include/gmock/gmock-generated-nice-strict.h",
+    "include/gmock/gmock-matchers.h",
+    "include/gmock/gmock-spec-builders.h",
+    "include/gmock/gmock.h",
+    "include/gmock/internal/gmock-generated-internal-utils.h",
+    "include/gmock/internal/gmock-internal-utils.h",
+    "include/gmock/internal/gmock-port.h",
+
+    #"src/gmock-all.cc",  # Not needed by our build.
+    "src/gmock-cardinalities.cc",
+    "src/gmock-internal-utils.cc",
+    "src/gmock-matchers.cc",
+    "src/gmock-spec-builders.cc",
+    "src/gmock.cc",
+  ]
+
+  # This project includes some stuff form gtest's guts.
+  include_dirs = [ "../gtest/include" ]
+
+  public_configs = [
+    ":gmock_config",
+    "//testing/gtest:gtest_config",
+  ]
+}
+
+static_library("gmock_main") {
+  # TODO http://crbug.com/412064 enable this flag all the time.
+  testonly = !is_component_build
+  sources = [ "src/gmock_main.cc" ]
+  deps = [ ":gmock" ]
+}
diff --git a/engine/src/flutter/build/secondary/testing/gtest/BUILD.gn b/engine/src/flutter/build/secondary/testing/gtest/BUILD.gn
new file mode 100644
index 00000000000..dad1b7d697b
--- /dev/null
+++ b/engine/src/flutter/build/secondary/testing/gtest/BUILD.gn
@@ -0,0 +1,132 @@
+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+config("gtest_config") {
+  visibility = [
+    ":*",
+    "//testing/gmock:*",  # gmock also shares this config.
+  ]
+
+  defines = [
+    # In order to allow regex matches in gtest to be shared between Windows
+    # and other systems, we tell gtest to always use it's internal engine.
+    "GTEST_HAS_POSIX_RE=0",
+
+    # Chrome doesn't support / require C++11, yet.
+    "GTEST_LANG_CXX11=0",
+  ]
+
+  # Gtest headers need to be able to find themselves.
+  include_dirs = [ "include" ]
+
+  if (is_win) {
+    cflags = [ "/wd4800" ]  # Unused variable warning.
+  }
+
+  if (is_posix) {
+    defines += [
+      # gtest isn't able to figure out when RTTI is disabled for gcc
+      # versions older than 4.3.2, and assumes it's enabled.  Our Mac
+      # and Linux builds disable RTTI, and cannot guarantee that the
+      # compiler will be 4.3.2. or newer.  The Mac, for example, uses
+      # 4.2.1 as that is the latest available on that platform.  gtest
+      # must be instructed that RTTI is disabled here, and for any
+      # direct dependents that might include gtest headers.
+      "GTEST_HAS_RTTI=0",
+    ]
+  }
+
+  if (is_android) {
+    defines += [
+      # We want gtest features that use tr1::tuple, but we currently
+      # don't support the variadic templates used by libstdc++'s
+      # implementation. gtest supports this scenario by providing its
+      # own implementation but we must opt in to it.
+      "GTEST_USE_OWN_TR1_TUPLE=1",
+
+      # GTEST_USE_OWN_TR1_TUPLE only works if GTEST_HAS_TR1_TUPLE is set.
+      # gtest r625 made it so that GTEST_HAS_TR1_TUPLE is set to 0
+      # automatically on android, so it has to be set explicitly here.
+      "GTEST_HAS_TR1_TUPLE=1",
+    ]
+  }
+}
+
+config("gtest_direct_config") {
+  visibility = [ ":*" ]
+  defines = [ "UNIT_TEST" ]
+}
+
+config("gtest_warnings") {
+  visibility = [ ":*" ]
+  if (is_win && is_clang) {
+    # The Mutex constructor initializer list in gtest-port.cc is incorrectly
+    # ordered. See
+    # https://groups.google.com/d/msg/googletestframework/S5uSV8L2TX8/U1FaTDa6J6sJ.
+    cflags = [ "-Wno-reorder" ]
+  }
+}
+
+static_library("gtest") {
+  # TODO http://crbug.com/412064 enable this flag all the time.
+  testonly = !is_component_build
+  sources = [
+    "include/gtest/gtest-death-test.h",
+    "include/gtest/gtest-message.h",
+    "include/gtest/gtest-param-test.h",
+    "include/gtest/gtest-printers.h",
+    "include/gtest/gtest-spi.h",
+    "include/gtest/gtest-test-part.h",
+    "include/gtest/gtest-typed-test.h",
+    "include/gtest/gtest.h",
+    "include/gtest/gtest_pred_impl.h",
+    "include/gtest/internal/gtest-death-test-internal.h",
+    "include/gtest/internal/gtest-filepath.h",
+    "include/gtest/internal/gtest-internal.h",
+    "include/gtest/internal/gtest-linked_ptr.h",
+    "include/gtest/internal/gtest-param-util-generated.h",
+    "include/gtest/internal/gtest-param-util.h",
+    "include/gtest/internal/gtest-port.h",
+    "include/gtest/internal/gtest-string.h",
+    "include/gtest/internal/gtest-tuple.h",
+    "include/gtest/internal/gtest-type-util.h",
+
+    #"gtest/src/gtest-all.cc",  # Not needed by our build.
+    "../multiprocess_func_list.cc",
+    "../multiprocess_func_list.h",
+    "../platform_test.h",
+    "src/gtest-death-test.cc",
+    "src/gtest-filepath.cc",
+    "src/gtest-internal-inl.h",
+    "src/gtest-port.cc",
+    "src/gtest-printers.cc",
+    "src/gtest-test-part.cc",
+    "src/gtest-typed-test.cc",
+    "src/gtest.cc",
+  ]
+
+  if (is_mac) {
+    sources += [
+      "../gtest_mac.h",
+      "../gtest_mac.mm",
+      "../platform_test_mac.mm",
+    ]
+  }
+
+  include_dirs = [ "." ]
+
+  all_dependent_configs = [ ":gtest_config" ]
+  public_configs = [ ":gtest_direct_config" ]
+
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
+  configs += [ ":gtest_warnings" ]
+}
+
+source_set("gtest_main") {
+  # TODO http://crbug.com/412064 enable this flag all the time.
+  testonly = !is_component_build
+  sources = [ "src/gtest_main.cc" ]
+  deps = [ ":gtest" ]
+}
diff --git a/engine/src/flutter/build/secondary/testing/libfuzzer/fuzzer_test.gni b/engine/src/flutter/build/secondary/testing/libfuzzer/fuzzer_test.gni
new file mode 100644
index 00000000000..8f8f3e750fe
--- /dev/null
+++ b/engine/src/flutter/build/secondary/testing/libfuzzer/fuzzer_test.gni
@@ -0,0 +1,11 @@
+# Copyright 2019 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# This is a dummy implementation to satisfy the ANGLE build, using the no-op
+# implementation from the real (Chromium) fuzzer_test.gni.
+template("fuzzer_test") {
+  not_needed(invoker, "*")
+  group(target_name) {
+  }
+}
diff --git a/engine/src/flutter/build/secondary/testing/test.gni b/engine/src/flutter/build/secondary/testing/test.gni
new file mode 100644
index 00000000000..ff724df0896
--- /dev/null
+++ b/engine/src/flutter/build/secondary/testing/test.gni
@@ -0,0 +1,6 @@
+# Copyright 2019 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# This is a dummy file to satisfy the ANGLE build. Flutter's use of ANGLE
+# doesn't actually require any of the real content.
diff --git a/engine/src/flutter/build/secondary/third_party/BUILD.gn b/engine/src/flutter/build/secondary/third_party/BUILD.gn
new file mode 100644
index 00000000000..c44ca40e888
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/BUILD.gn
@@ -0,0 +1,9 @@
+# Copyright 2016 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+source_set("fontconfig") {
+  if (is_linux) {
+    libs = [ "fontconfig" ]
+  }
+}
diff --git a/engine/src/flutter/build/secondary/third_party/android_ndk/BUILD.gn b/engine/src/flutter/build/secondary/third_party/android_ndk/BUILD.gn
new file mode 100644
index 00000000000..697d2873a5e
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/android_ndk/BUILD.gn
@@ -0,0 +1,8 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+source_set("cpu_features") {
+  public_configs = [ "//third_party/android_tools:cpu_features_include" ]
+  deps = [ "//third_party/android_tools:cpu_features" ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/android_tools/BUILD.gn b/engine/src/flutter/build/secondary/third_party/android_tools/BUILD.gn
new file mode 100644
index 00000000000..574472afdb2
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/android_tools/BUILD.gn
@@ -0,0 +1,19 @@
+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import("//build/config/android/rules.gni")
+
+config("cpu_features_include") {
+  include_dirs = [ "ndk/sources/android/cpufeatures" ]
+}
+
+# This is the GN version of
+# //build/android/ndk.gyp:cpu_features
+source_set("cpu_features") {
+  sources = [ "ndk/sources/android/cpufeatures/cpu-features.c" ]
+  public_configs = [ ":cpu_features_include" ]
+
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/benchmark/BUILD.gn b/engine/src/flutter/build/secondary/third_party/benchmark/BUILD.gn
new file mode 100644
index 00000000000..f88d6bf0c68
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/benchmark/BUILD.gn
@@ -0,0 +1,60 @@
+# Copyright 2016 The Fuchsia Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+config("benchmark_config") {
+  visibility = [ ":*" ]
+  include_dirs = [ "include" ]
+}
+static_library("benchmark") {
+  testonly = true
+
+  sources = [
+    "//third_party/benchmark/src/arraysize.h",
+    "//third_party/benchmark/src/benchmark.cc",
+    "//third_party/benchmark/src/benchmark_api_internal.cc",
+    "//third_party/benchmark/src/benchmark_api_internal.h",
+    "//third_party/benchmark/src/benchmark_main.cc",
+    "//third_party/benchmark/src/benchmark_name.cc",
+    "//third_party/benchmark/src/benchmark_register.cc",
+    "//third_party/benchmark/src/benchmark_register.h",
+    "//third_party/benchmark/src/benchmark_runner.cc",
+    "//third_party/benchmark/src/benchmark_runner.h",
+    "//third_party/benchmark/src/check.h",
+    "//third_party/benchmark/src/colorprint.cc",
+    "//third_party/benchmark/src/colorprint.h",
+    "//third_party/benchmark/src/commandlineflags.cc",
+    "//third_party/benchmark/src/commandlineflags.h",
+    "//third_party/benchmark/src/complexity.cc",
+    "//third_party/benchmark/src/complexity.h",
+    "//third_party/benchmark/src/console_reporter.cc",
+    "//third_party/benchmark/src/counter.cc",
+    "//third_party/benchmark/src/counter.h",
+    "//third_party/benchmark/src/csv_reporter.cc",
+    "//third_party/benchmark/src/cycleclock.h",
+    "//third_party/benchmark/src/internal_macros.h",
+    "//third_party/benchmark/src/json_reporter.cc",
+    "//third_party/benchmark/src/log.h",
+    "//third_party/benchmark/src/mutex.h",
+    "//third_party/benchmark/src/perf_counters.cc",
+    "//third_party/benchmark/src/perf_counters.h",
+    "//third_party/benchmark/src/re.h",
+    "//third_party/benchmark/src/reporter.cc",
+    "//third_party/benchmark/src/sleep.cc",
+    "//third_party/benchmark/src/sleep.h",
+    "//third_party/benchmark/src/statistics.cc",
+    "//third_party/benchmark/src/statistics.h",
+    "//third_party/benchmark/src/string_util.cc",
+    "//third_party/benchmark/src/string_util.h",
+    "//third_party/benchmark/src/sysinfo.cc",
+    "//third_party/benchmark/src/sysinfo.h",
+    "//third_party/benchmark/src/thread_manager.h",
+    "//third_party/benchmark/src/thread_timer.h",
+    "//third_party/benchmark/src/timers.cc",
+    "//third_party/benchmark/src/timers.h",
+  ]
+  public_configs = [ ":benchmark_config" ]
+  defines = [
+    "HAVE_STD_REGEX",
+    "HAVE_THREAD_SAFETY_ATTRIBUTES",
+  ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/cpu-features/BUILD.gn b/engine/src/flutter/build/secondary/third_party/cpu-features/BUILD.gn
new file mode 100644
index 00000000000..dadee56df8c
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/cpu-features/BUILD.gn
@@ -0,0 +1,8 @@
+# Copyright 2016 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+source_set("cpu-features") {
+  public_configs = [ "//third_party/android_tools:cpu_features_include" ]
+  deps = [ "//third_party/android_tools:cpu_features" ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/dart/pkg/meta/BUILD.gn b/engine/src/flutter/build/secondary/third_party/dart/pkg/meta/BUILD.gn
new file mode 100644
index 00000000000..3ad0e03f66b
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/dart/pkg/meta/BUILD.gn
@@ -0,0 +1,26 @@
+# Copyright 2021 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# TODO(flutter/flutter#85356): This file was originally generated by the
+# fuchsia.git script: `package_importer.py`. The generated `BUILD.gn` files were
+# copied to the flutter repo to support `dart_library` targets used for
+# Flutter-Fuchsia integration tests. This file can be maintained by hand, but it
+# would be better to implement a script for Flutter, to either generate these
+# BUILD.gn files or dynamically generate the GN targets.
+
+import("//flutter/tools/fuchsia/dart/dart_library.gni")
+
+dart_library("meta") {
+  package_name = "meta"
+
+  language_version = "2.12"
+
+  deps = []
+
+  sources = [
+    "dart2js.dart",
+    "meta.dart",
+    "meta_meta.dart",
+  ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/dart/third_party/pkg/args/BUILD.gn b/engine/src/flutter/build/secondary/third_party/dart/third_party/pkg/args/BUILD.gn
new file mode 100644
index 00000000000..e25404362f6
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/dart/third_party/pkg/args/BUILD.gn
@@ -0,0 +1,35 @@
+# Copyright 2021 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# TODO(flutter/flutter#85356): This file was originally generated by the
+# fuchsia.git script: `package_importer.py`. The generated `BUILD.gn` files were
+# copied to the flutter repo to support `dart_library` targets used for
+# Flutter-Fuchsia integration tests. This file can be maintained by hand, but it
+# would be better to implement a script for Flutter, to either generate these
+# BUILD.gn files or dynamically generate the GN targets.
+
+import("//flutter/tools/fuchsia/dart/dart_library.gni")
+
+dart_library("args") {
+  package_name = "args"
+
+  language_version = "2.12"
+
+  deps = []
+
+  sources = [
+    "args.dart",
+    "command_runner.dart",
+    "src/allow_anything_parser.dart",
+    "src/arg_parser.dart",
+    "src/arg_parser_exception.dart",
+    "src/arg_results.dart",
+    "src/help_command.dart",
+    "src/option.dart",
+    "src/parser.dart",
+    "src/usage.dart",
+    "src/usage_exception.dart",
+    "src/utils.dart",
+  ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/dart/third_party/pkg/collection/BUILD.gn b/engine/src/flutter/build/secondary/third_party/dart/third_party/pkg/collection/BUILD.gn
new file mode 100644
index 00000000000..092624f4bed
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/dart/third_party/pkg/collection/BUILD.gn
@@ -0,0 +1,51 @@
+# Copyright 2021 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# TODO(flutter/flutter#85356): This file was originally generated by the
+# fuchsia.git script: `package_importer.py`. The generated `BUILD.gn` files were
+# copied to the flutter repo to support `dart_library` targets used for
+# Flutter-Fuchsia integration tests. This file can be maintained by hand, but it
+# would be better to implement a script for Flutter, to either generate these
+# BUILD.gn files or dynamically generate the GN targets.
+
+import("//flutter/tools/fuchsia/dart/dart_library.gni")
+
+dart_library("collection") {
+  package_name = "collection"
+
+  language_version = "2.12"
+
+  deps = []
+
+  sources = [
+    "algorithms.dart",
+    "collection.dart",
+    "equality.dart",
+    "iterable_zip.dart",
+    "priority_queue.dart",
+    "src/algorithms.dart",
+    "src/canonicalized_map.dart",
+    "src/combined_wrappers/combined_iterable.dart",
+    "src/combined_wrappers/combined_iterator.dart",
+    "src/combined_wrappers/combined_list.dart",
+    "src/combined_wrappers/combined_map.dart",
+    "src/comparators.dart",
+    "src/empty_unmodifiable_set.dart",
+    "src/equality.dart",
+    "src/equality_map.dart",
+    "src/equality_set.dart",
+    "src/functions.dart",
+    "src/iterable_extensions.dart",
+    "src/iterable_zip.dart",
+    "src/list_extensions.dart",
+    "src/priority_queue.dart",
+    "src/queue_list.dart",
+    "src/union_set.dart",
+    "src/union_set_controller.dart",
+    "src/unmodifiable_wrappers.dart",
+    "src/utils.dart",
+    "src/wrappers.dart",
+    "wrappers.dart",
+  ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/dart/third_party/pkg/logging/BUILD.gn b/engine/src/flutter/build/secondary/third_party/dart/third_party/pkg/logging/BUILD.gn
new file mode 100644
index 00000000000..73baa076361
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/dart/third_party/pkg/logging/BUILD.gn
@@ -0,0 +1,27 @@
+# Copyright 2021 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# TODO(flutter/flutter#85356): This file was originally generated by the
+# fuchsia.git script: `package_importer.py`. The generated `BUILD.gn` files were
+# copied to the flutter repo to support `dart_library` targets used for
+# Flutter-Fuchsia integration tests. This file can be maintained by hand, but it
+# would be better to implement a script for Flutter, to either generate these
+# BUILD.gn files or dynamically generate the GN targets.
+
+import("//flutter/tools/fuchsia/dart/dart_library.gni")
+
+dart_library("logging") {
+  package_name = "logging"
+
+  language_version = "2.12"
+
+  deps = []
+
+  sources = [
+    "logging.dart",
+    "src/level.dart",
+    "src/log_record.dart",
+    "src/logger.dart",
+  ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/dart/third_party/pkg/matcher/BUILD.gn b/engine/src/flutter/build/secondary/third_party/dart/third_party/pkg/matcher/BUILD.gn
new file mode 100644
index 00000000000..9bd84e15f70
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/dart/third_party/pkg/matcher/BUILD.gn
@@ -0,0 +1,55 @@
+# Copyright 2021 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# TODO(flutter/flutter#85356): This file was originally generated by the
+# fuchsia.git script: `package_importer.py`. The generated `BUILD.gn` files were
+# copied to the flutter repo to support `dart_library` targets used for
+# Flutter-Fuchsia integration tests. This file can be maintained by hand, but it
+# would be better to implement a script for Flutter, to either generate these
+# BUILD.gn files or dynamically generate the GN targets.
+
+import("//flutter/tools/fuchsia/dart/dart_library.gni")
+
+dart_library("matcher") {
+  package_name = "matcher"
+
+  language_version = "2.12"
+
+  deps = [ "//third_party/dart/third_party/pkg/stack_trace" ]
+
+  sources = [
+    "expect.dart",
+    "matcher.dart",
+    "mirror_matchers.dart",
+    "src/core_matchers.dart",
+    "src/custom_matcher.dart",
+    "src/description.dart",
+    "src/equals_matcher.dart",
+    "src/error_matchers.dart",
+    "src/expect/async_matcher.dart",
+    "src/expect/expect.dart",
+    "src/expect/expect_async.dart",
+    "src/expect/future_matchers.dart",
+    "src/expect/never_called.dart",
+    "src/expect/prints_matcher.dart",
+    "src/expect/stream_matcher.dart",
+    "src/expect/stream_matchers.dart",
+    "src/expect/throws_matcher.dart",
+    "src/expect/throws_matchers.dart",
+    "src/expect/util/placeholder.dart",
+    "src/expect/util/pretty_print.dart",
+    "src/feature_matcher.dart",
+    "src/having_matcher.dart",
+    "src/interfaces.dart",
+    "src/iterable_matchers.dart",
+    "src/map_matchers.dart",
+    "src/numeric_matchers.dart",
+    "src/operator_matchers.dart",
+    "src/order_matchers.dart",
+    "src/pretty_print.dart",
+    "src/string_matchers.dart",
+    "src/type_matcher.dart",
+    "src/util.dart",
+  ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/dart/third_party/pkg/path/BUILD.gn b/engine/src/flutter/build/secondary/third_party/dart/third_party/pkg/path/BUILD.gn
new file mode 100644
index 00000000000..2e692b66eb9
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/dart/third_party/pkg/path/BUILD.gn
@@ -0,0 +1,36 @@
+# Copyright 2021 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# TODO(flutter/flutter#85356): This file was originally generated by the
+# fuchsia.git script: `package_importer.py`. The generated `BUILD.gn` files were
+# copied to the flutter repo to support `dart_library` targets used for
+# Flutter-Fuchsia integration tests. This file can be maintained by hand, but it
+# would be better to implement a script for Flutter, to either generate these
+# BUILD.gn files or dynamically generate the GN targets.
+
+import("//flutter/tools/fuchsia/dart/dart_library.gni")
+
+dart_library("path") {
+  package_name = "path"
+
+  language_version = "2.12"
+
+  deps = []
+
+  sources = [
+    "path.dart",
+    "src/characters.dart",
+    "src/context.dart",
+    "src/internal_style.dart",
+    "src/parsed_path.dart",
+    "src/path_exception.dart",
+    "src/path_map.dart",
+    "src/path_set.dart",
+    "src/style.dart",
+    "src/style/posix.dart",
+    "src/style/url.dart",
+    "src/style/windows.dart",
+    "src/utils.dart",
+  ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/dart/third_party/pkg/stack_trace/BUILD.gn b/engine/src/flutter/build/secondary/third_party/dart/third_party/pkg/stack_trace/BUILD.gn
new file mode 100644
index 00000000000..10dd2983dd0
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/dart/third_party/pkg/stack_trace/BUILD.gn
@@ -0,0 +1,33 @@
+# Copyright 2021 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# TODO(flutter/flutter#85356): This file was originally generated by the
+# fuchsia.git script: `package_importer.py`. The generated `BUILD.gn` files were
+# copied to the flutter repo to support `dart_library` targets used for
+# Flutter-Fuchsia integration tests. This file can be maintained by hand, but it
+# would be better to implement a script for Flutter, to either generate these
+# BUILD.gn files or dynamically generate the GN targets.
+
+import("//flutter/tools/fuchsia/dart/dart_library.gni")
+
+dart_library("stack_trace") {
+  package_name = "stack_trace"
+
+  language_version = "2.12"
+
+  deps = [ "//third_party/dart/third_party/pkg/path" ]
+
+  sources = [
+    "src/chain.dart",
+    "src/frame.dart",
+    "src/lazy_chain.dart",
+    "src/lazy_trace.dart",
+    "src/stack_zone_specification.dart",
+    "src/trace.dart",
+    "src/unparsed_frame.dart",
+    "src/utils.dart",
+    "src/vm_trace.dart",
+    "stack_trace.dart",
+  ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/expat/BUILD.gn b/engine/src/flutter/build/secondary/third_party/expat/BUILD.gn
new file mode 100644
index 00000000000..316ec274443
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/expat/BUILD.gn
@@ -0,0 +1,26 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+config("expat_config") {
+  include_dirs = [
+    "expat/lib",
+    "//flutter/build/secondary/third_party/expat/expat_config",
+  ]
+
+  defines = [
+    "XML_STATIC",
+    "XML_DEV_URANDOM",
+  ]
+}
+
+static_library("expat") {
+  sources = [
+    "expat/lib/expat.h",
+    "expat/lib/xmlparse.c",
+    "expat/lib/xmlrole.c",
+    "expat/lib/xmltok.c",
+  ]
+
+  public_configs = [ ":expat_config" ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/expat/expat_config/expat_config.h b/engine/src/flutter/build/secondary/third_party/expat/expat_config/expat_config.h
new file mode 100644
index 00000000000..d02d0f6005c
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/expat/expat_config/expat_config.h
@@ -0,0 +1,14 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#define BYTEORDER 1234
+#define HAVE_INTTYPES_H 1
+#define HAVE_MEMORY_H 1
+#define HAVE_STDINT_H 1
+#define HAVE_STDLIB_H 1
+#define HAVE_STRING_H 1
+#define STDC_HEADERS 1
+#define XML_CONTEXT_BYTES 1024
+#define XML_DTD 1
+#define XML_NS 1
diff --git a/engine/src/flutter/build/secondary/third_party/flatbuffers/BUILD.gn b/engine/src/flutter/build/secondary/third_party/flatbuffers/BUILD.gn
new file mode 100644
index 00000000000..502be760175
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/flatbuffers/BUILD.gn
@@ -0,0 +1,100 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+_src_root = "//third_party/flatbuffers"
+
+config("flatbuffers_public_configs") {
+  include_dirs = [ "$_src_root/include" ]
+
+  cflags = [ "-Wno-newline-eof" ]
+}
+
+source_set("flatbuffers") {
+  sources = [
+    "$_src_root/include/flatbuffers/allocator.h",
+    "$_src_root/include/flatbuffers/array.h",
+    "$_src_root/include/flatbuffers/base.h",
+    "$_src_root/include/flatbuffers/bfbs_generator.h",
+    "$_src_root/include/flatbuffers/buffer.h",
+    "$_src_root/include/flatbuffers/buffer_ref.h",
+    "$_src_root/include/flatbuffers/default_allocator.h",
+    "$_src_root/include/flatbuffers/detached_buffer.h",
+    "$_src_root/include/flatbuffers/flatbuffer_builder.h",
+    "$_src_root/include/flatbuffers/flatbuffers.h",
+    "$_src_root/include/flatbuffers/flex_flat_util.h",
+    "$_src_root/include/flatbuffers/flexbuffers.h",
+    "$_src_root/include/flatbuffers/hash.h",
+    "$_src_root/include/flatbuffers/idl.h",
+    "$_src_root/include/flatbuffers/minireflect.h",
+    "$_src_root/include/flatbuffers/reflection.h",
+    "$_src_root/include/flatbuffers/reflection_generated.h",
+    "$_src_root/include/flatbuffers/registry.h",
+    "$_src_root/include/flatbuffers/stl_emulation.h",
+    "$_src_root/include/flatbuffers/string.h",
+    "$_src_root/include/flatbuffers/struct.h",
+    "$_src_root/include/flatbuffers/table.h",
+    "$_src_root/include/flatbuffers/util.h",
+    "$_src_root/include/flatbuffers/vector.h",
+    "$_src_root/include/flatbuffers/vector_downward.h",
+    "$_src_root/include/flatbuffers/verifier.h",
+    "$_src_root/src/idl_gen_text.cpp",
+    "$_src_root/src/idl_parser.cpp",
+    "$_src_root/src/reflection.cpp",
+    "$_src_root/src/util.cpp",
+  ]
+
+  public_configs = [ ":flatbuffers_public_configs" ]
+}
+
+executable("flatc") {
+  sources = [
+    "$_src_root/grpc/src/compiler/cpp_generator.cc",
+    "$_src_root/grpc/src/compiler/cpp_generator.h",
+    "$_src_root/grpc/src/compiler/go_generator.cc",
+    "$_src_root/grpc/src/compiler/go_generator.h",
+    "$_src_root/grpc/src/compiler/java_generator.cc",
+    "$_src_root/grpc/src/compiler/java_generator.h",
+    "$_src_root/grpc/src/compiler/python_generator.cc",
+    "$_src_root/grpc/src/compiler/python_generator.h",
+    "$_src_root/grpc/src/compiler/schema_interface.h",
+    "$_src_root/grpc/src/compiler/swift_generator.cc",
+    "$_src_root/grpc/src/compiler/swift_generator.h",
+    "$_src_root/grpc/src/compiler/ts_generator.cc",
+    "$_src_root/grpc/src/compiler/ts_generator.h",
+    "$_src_root/include/flatbuffers/code_generators.h",
+    "$_src_root/src/annotated_binary_text_gen.cpp",
+    "$_src_root/src/annotated_binary_text_gen.h",
+    "$_src_root/src/bfbs_gen.h",
+    "$_src_root/src/bfbs_gen_lua.cpp",
+    "$_src_root/src/bfbs_gen_lua.h",
+    "$_src_root/src/bfbs_namer.h",
+    "$_src_root/src/binary_annotator.cpp",
+    "$_src_root/src/binary_annotator.h",
+    "$_src_root/src/code_generators.cpp",
+    "$_src_root/src/flatc.cpp",
+    "$_src_root/src/flatc_main.cpp",
+    "$_src_root/src/idl_gen_cpp.cpp",
+    "$_src_root/src/idl_gen_csharp.cpp",
+    "$_src_root/src/idl_gen_dart.cpp",
+    "$_src_root/src/idl_gen_fbs.cpp",
+    "$_src_root/src/idl_gen_go.cpp",
+    "$_src_root/src/idl_gen_grpc.cpp",
+    "$_src_root/src/idl_gen_java.cpp",
+    "$_src_root/src/idl_gen_json_schema.cpp",
+    "$_src_root/src/idl_gen_kotlin.cpp",
+    "$_src_root/src/idl_gen_lobster.cpp",
+    "$_src_root/src/idl_gen_lua.cpp",
+    "$_src_root/src/idl_gen_php.cpp",
+    "$_src_root/src/idl_gen_python.cpp",
+    "$_src_root/src/idl_gen_rust.cpp",
+    "$_src_root/src/idl_gen_swift.cpp",
+    "$_src_root/src/idl_gen_ts.cpp",
+    "$_src_root/src/idl_namer.h",
+    "$_src_root/src/namer.h",
+  ]
+
+  include_dirs = [ "$_src_root/grpc" ]
+
+  deps = [ ":flatbuffers" ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/flatbuffers/flatbuffers.gni b/engine/src/flutter/build/secondary/third_party/flatbuffers/flatbuffers.gni
new file mode 100644
index 00000000000..ae636d64aee
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/flatbuffers/flatbuffers.gni
@@ -0,0 +1,51 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import("//build/compiled_action.gni")
+
+template("flatbuffers") {
+  assert(defined(invoker.flatbuffers),
+         "Flatbuffer schema files must be specified.")
+
+  flatc_target_name = "flatc_$target_name"
+  compiled_action_foreach(flatc_target_name) {
+    tool = "//third_party/flatbuffers:flatc"
+    sources = invoker.flatbuffers
+    outputs = [ "$target_gen_dir/{{source_name_part}}_flatbuffers.h" ]
+    args = [
+      "--warnings-as-errors",
+      "--cpp",
+      "--cpp-std",
+      "c++17",
+      "--cpp-static-reflection",
+      "--gen-object-api",
+      "--filename-suffix",
+      "_flatbuffers",
+      "-o",
+      rebase_path(target_gen_dir, root_build_dir),
+      "{{source}}",
+    ]
+  }
+
+  source_set(target_name) {
+    forward_variables_from(invoker,
+                           "*",
+                           [
+                             "flatbuffers",
+                             "sources",
+                             "deps",
+                           ])
+    sources = get_target_outputs(":$flatc_target_name")
+    if (defined(invoker.sources)) {
+      sources += invoker.sources
+    }
+    deps = [
+      ":$flatc_target_name",
+      "//third_party/flatbuffers",
+    ]
+    if (defined(invoker.deps)) {
+      deps += invoker.deps
+    }
+  }
+}
diff --git a/engine/src/flutter/build/secondary/third_party/googletest/BUILD.gn b/engine/src/flutter/build/secondary/third_party/googletest/BUILD.gn
new file mode 100644
index 00000000000..72f87cc4749
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/googletest/BUILD.gn
@@ -0,0 +1,319 @@
+# Copyright 2018 The Fuchsia Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+if (is_fuchsia) {
+  import("//build/fuchsia/sdk.gni")
+}
+
+config("gtest_private_config") {
+  visibility = [ ":*" ]
+  include_dirs = [ "googletest" ]
+}
+
+config("gtest_config") {
+  include_dirs = [ "googletest/include" ]
+}
+
+static_library("gtest") {
+  testonly = true
+  public = [
+    "googletest/include/gtest/gtest-spi.h",
+    "googletest/include/gtest/gtest.h",
+  ]
+  sources = [
+    "googletest/include/gtest/gtest-death-test.h",
+    "googletest/include/gtest/gtest-message.h",
+    "googletest/include/gtest/gtest-param-test.h",
+    "googletest/include/gtest/gtest-printers.h",
+    "googletest/include/gtest/gtest-test-part.h",
+    "googletest/include/gtest/gtest-typed-test.h",
+    "googletest/include/gtest/gtest_pred_impl.h",
+    "googletest/include/gtest/gtest_prod.h",
+    "googletest/include/gtest/internal/custom/gtest-port.h",
+    "googletest/include/gtest/internal/custom/gtest-printers.h",
+    "googletest/include/gtest/internal/custom/gtest.h",
+    "googletest/include/gtest/internal/gtest-death-test-internal.h",
+    "googletest/include/gtest/internal/gtest-filepath.h",
+    "googletest/include/gtest/internal/gtest-internal.h",
+    "googletest/include/gtest/internal/gtest-linked_ptr.h",
+    "googletest/include/gtest/internal/gtest-param-util-generated.h",
+    "googletest/include/gtest/internal/gtest-param-util.h",
+    "googletest/include/gtest/internal/gtest-port-arch.h",
+    "googletest/include/gtest/internal/gtest-port.h",
+    "googletest/include/gtest/internal/gtest-string.h",
+    "googletest/include/gtest/internal/gtest-tuple.h",
+    "googletest/include/gtest/internal/gtest-type-util.h",
+    "googletest/src/gtest-all.cc",
+    "googletest/src/gtest-death-test.cc",
+    "googletest/src/gtest-filepath.cc",
+    "googletest/src/gtest-internal-inl.h",
+    "googletest/src/gtest-matchers.cc",
+    "googletest/src/gtest-port.cc",
+    "googletest/src/gtest-printers.cc",
+    "googletest/src/gtest-test-part.cc",
+    "googletest/src/gtest-typed-test.cc",
+    "googletest/src/gtest.cc",
+  ]
+  sources -= [ "googletest/src/gtest-all.cc" ]
+  public_configs = [ ":gtest_config" ]
+  configs += [ ":gtest_private_config" ]
+
+  if (is_fuchsia) {
+    if (using_fuchsia_sdk) {
+      deps = [
+        "$fuchsia_sdk_root/pkg:fdio",
+        "$fuchsia_sdk_root/pkg:zx",
+      ]
+    } else {
+      deps = [
+        "//zircon/public/lib/fdio",
+        "//zircon/public/lib/zx",
+      ]
+    }
+  }
+}
+
+# Library that defines the FRIEND_TEST macro.
+source_set("gtest_prod") {
+  testonly = false
+  public = [ "googletest/include/gtest/gtest_prod.h" ]
+  public_configs = [ ":gtest_config" ]
+}
+
+static_library("gtest_main") {
+  testonly = true
+  sources = [ "googletest/src/gtest_main.cc" ]
+  public_deps = [ ":gtest" ]
+}
+
+executable("gtest_all_test") {
+  testonly = true
+  sources = [
+    "googletest/test/gtest-death-test_test.cc",
+    "googletest/test/gtest-filepath_test.cc",
+    "googletest/test/gtest-linked_ptr_test.cc",
+    "googletest/test/gtest-message_test.cc",
+    "googletest/test/gtest-options_test.cc",
+    "googletest/test/gtest-port_test.cc",
+    "googletest/test/gtest-printers_test.cc",
+    "googletest/test/gtest-test-part_test.cc",
+    "googletest/test/gtest-typed-test2_test.cc",
+    "googletest/test/gtest-typed-test_test.cc",
+    "googletest/test/gtest-typed-test_test.h",
+    "googletest/test/gtest_main_unittest.cc",
+    "googletest/test/gtest_pred_impl_unittest.cc",
+    "googletest/test/gtest_prod_test.cc",
+    "googletest/test/gtest_unittest.cc",
+    "googletest/test/production.cc",
+    "googletest/test/production.h",
+  ]
+  configs += [ ":gtest_private_config" ]
+  deps = [
+    ":gtest",
+    ":gtest_main",
+  ]
+}
+
+executable("gtest_environment_test") {
+  testonly = true
+  sources = [ "googletest/test/gtest_environment_test.cc" ]
+  configs += [ ":gtest_private_config" ]
+  deps = [ ":gtest" ]
+}
+
+executable("gtest_listener_test") {
+  testonly = true
+  sources = [ "googletest/test/gtest-listener_test.cc" ]
+  deps = [ ":gtest" ]
+}
+
+executable("gtest_no_test") {
+  testonly = true
+  sources = [ "googletest/test/gtest_no_test_unittest.cc" ]
+  deps = [ ":gtest" ]
+}
+
+executable("gtest_param_test") {
+  testonly = true
+  sources = [
+    "googletest/test/gtest-param-test2_test.cc",
+    "googletest/test/gtest-param-test_test.cc",
+    "googletest/test/gtest-param-test_test.h",
+  ]
+  configs += [ ":gtest_private_config" ]
+  deps = [ ":gtest" ]
+}
+
+executable("gtest_premature_exit_test") {
+  testonly = true
+  sources = [ "googletest/test/gtest_premature_exit_test.cc" ]
+  deps = [ ":gtest" ]
+}
+
+executable("gtest_repeat_test") {
+  testonly = true
+  sources = [ "googletest/test/gtest_repeat_test.cc" ]
+  configs += [ ":gtest_private_config" ]
+  deps = [ ":gtest" ]
+}
+
+executable("gtest_sole_header_test") {
+  testonly = true
+  sources = [ "googletest/test/gtest_sole_header_test.cc" ]
+  deps = [
+    ":gtest",
+    ":gtest_main",
+  ]
+}
+
+executable("gtest_stress_test") {
+  testonly = true
+  sources = [ "googletest/test/gtest_stress_test.cc" ]
+  configs += [ ":gtest_private_config" ]
+  deps = [ ":gtest" ]
+}
+
+executable("gtest_unittest_api_test") {
+  testonly = true
+  sources = [ "googletest/test/gtest-unittest-api_test.cc" ]
+  deps = [ ":gtest" ]
+}
+
+group("gtest_all_tests") {
+  testonly = true
+  deps = [
+    ":gtest_all_test",
+    ":gtest_environment_test",
+    ":gtest_listener_test",
+    ":gtest_no_test",
+    ":gtest_param_test",
+    ":gtest_premature_exit_test",
+    ":gtest_repeat_test",
+    ":gtest_sole_header_test",
+    ":gtest_stress_test",
+    ":gtest_unittest_api_test",
+  ]
+}
+
+config("gmock_private_config") {
+  visibility = [ ":*" ]
+  include_dirs = [ "googlemock" ]
+}
+
+config("gmock_config") {
+  include_dirs = [ "googlemock/include" ]
+
+  cflags_cc = [
+    # The MOCK_METHODn() macros do not specify "override", which triggers this
+    # warning in users: "error: 'Method' overrides a member function but is not
+    # marked 'override' [-Werror,-Winconsistent-missing-override]". Suppress
+    # these warnings until https://github.com/google/googletest/issues/533 is
+    # fixed.
+    "-Wno-inconsistent-missing-override",
+  ]
+}
+
+static_library("gmock") {
+  testonly = true
+  public = [ "googlemock/include/gmock/gmock.h" ]
+  sources = [
+    "googlemock/include/gmock/gmock-actions.h",
+    "googlemock/include/gmock/gmock-cardinalities.h",
+    "googlemock/include/gmock/gmock-generated-actions.h",
+    "googlemock/include/gmock/gmock-generated-function-mockers.h",
+    "googlemock/include/gmock/gmock-generated-matchers.h",
+    "googlemock/include/gmock/gmock-generated-nice-strict.h",
+    "googlemock/include/gmock/gmock-matchers.h",
+    "googlemock/include/gmock/gmock-more-actions.h",
+    "googlemock/include/gmock/gmock-more-matchers.h",
+    "googlemock/include/gmock/gmock-spec-builders.h",
+    "googlemock/include/gmock/internal/custom/gmock-generated-actions.h",
+    "googlemock/include/gmock/internal/custom/gmock-matchers.h",
+    "googlemock/include/gmock/internal/custom/gmock-port.h",
+    "googlemock/include/gmock/internal/gmock-generated-internal-utils.h",
+    "googlemock/include/gmock/internal/gmock-internal-utils.h",
+    "googlemock/include/gmock/internal/gmock-port.h",
+    "googlemock/src/gmock-all.cc",
+    "googlemock/src/gmock-cardinalities.cc",
+    "googlemock/src/gmock-internal-utils.cc",
+    "googlemock/src/gmock-matchers.cc",
+    "googlemock/src/gmock-spec-builders.cc",
+    "googlemock/src/gmock.cc",
+  ]
+  sources -= [ "googlemock/src/gmock-all.cc" ]
+  public_configs = [ ":gmock_config" ]
+  configs += [ ":gmock_private_config" ]
+  deps = [ ":gtest" ]
+}
+
+static_library("gmock_main") {
+  testonly = true
+  sources = [ "googlemock/src/gmock_main.cc" ]
+  public_deps = [
+    ":gmock",
+    ":gtest",
+  ]
+}
+
+executable("gmock_all_test") {
+  testonly = true
+  sources = [
+    "googlemock/test/gmock-actions_test.cc",
+    "googlemock/test/gmock-cardinalities_test.cc",
+    "googlemock/test/gmock-generated-actions_test.cc",
+    "googlemock/test/gmock-generated-function-mockers_test.cc",
+    "googlemock/test/gmock-generated-internal-utils_test.cc",
+    "googlemock/test/gmock-generated-matchers_test.cc",
+    "googlemock/test/gmock-internal-utils_test.cc",
+    "googlemock/test/gmock-matchers_test.cc",
+    "googlemock/test/gmock-more-actions_test.cc",
+    "googlemock/test/gmock-nice-strict_test.cc",
+    "googlemock/test/gmock-port_test.cc",
+    "googlemock/test/gmock-spec-builders_test.cc",
+    "googlemock/test/gmock_test.cc",
+  ]
+  configs += [
+    ":gmock_private_config",
+    ":gtest_private_config",
+  ]
+  deps = [
+    ":gmock",
+    ":gmock_main",
+    ":gtest",
+  ]
+}
+
+executable("gmock_link_test") {
+  testonly = true
+  sources = [
+    "googlemock/test/gmock_link2_test.cc",
+    "googlemock/test/gmock_link_test.cc",
+    "googlemock/test/gmock_link_test.h",
+  ]
+  configs += [ ":gmock_private_config" ]
+  deps = [
+    ":gmock",
+    ":gmock_main",
+    ":gtest",
+  ]
+}
+
+executable("gmock_stress_test") {
+  testonly = true
+  sources = [ "googlemock/test/gmock_stress_test.cc" ]
+  configs += [ ":gmock_private_config" ]
+  deps = [
+    ":gmock",
+    ":gtest",
+  ]
+}
+
+group("gmock_all_tests") {
+  testonly = true
+  deps = [
+    ":gmock_all_test",
+    ":gmock_link_test",
+    ":gmock_stress_test",
+  ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/imgui/BUILD.gn b/engine/src/flutter/build/secondary/third_party/imgui/BUILD.gn
new file mode 100644
index 00000000000..dadc4eec3ec
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/imgui/BUILD.gn
@@ -0,0 +1,48 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+source_root = "//third_party/imgui"
+
+source_set("imgui") {
+  public = [
+    "$source_root/imgui.h",
+    "$source_root/imgui_internal.h",
+    "$source_root/imstb_rectpack.h",
+    "$source_root/imstb_textedit.h",
+    "$source_root/imstb_truetype.h",
+  ]
+
+  include_dirs = [ "$source_root" ]
+
+  sources = [
+    "$source_root/imgui.cpp",
+    "$source_root/imgui.h",
+    "$source_root/imgui_demo.cpp",
+    "$source_root/imgui_draw.cpp",
+    "$source_root/imgui_internal.h",
+    "$source_root/imgui_tables.cpp",
+    "$source_root/imgui_widgets.cpp",
+    "$source_root/imstb_rectpack.h",
+    "$source_root/imstb_textedit.h",
+    "$source_root/imstb_truetype.h",
+  ]
+}
+
+config("imgui_headers") {
+  include_dirs = [ "$source_root" ]
+}
+
+source_set("imgui_glfw") {
+  public_deps = [
+    ":imgui",
+    "//flutter/third_party/glfw",
+  ]
+
+  public_configs = [ ":imgui_headers" ]
+
+  sources = [
+    "$source_root/backends/imgui_impl_glfw.cpp",
+    "$source_root/backends/imgui_impl_glfw.h",
+  ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/inja/BUILD.gn b/engine/src/flutter/build/secondary/third_party/inja/BUILD.gn
new file mode 100644
index 00000000000..59345eb31ce
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/inja/BUILD.gn
@@ -0,0 +1,43 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+source_root = "//third_party/inja"
+
+config("inja_public_config") {
+  include_dirs = [ "$source_root/include" ]
+
+  if (is_clang) {
+    cflags_cc = [
+      "-Wno-unused-variable",
+      "-Wno-newline-eof",
+    ]
+  }
+
+  defines = [ "INJA_NOEXCEPTION=1" ]
+}
+
+source_set("inja") {
+  public_configs = [ ":inja_public_config" ]
+
+  public = [ "$source_root/include/inja/inja.hpp" ]
+
+  sources = [
+    "$source_root/include/inja/config.hpp",
+    "$source_root/include/inja/environment.hpp",
+    "$source_root/include/inja/exceptions.hpp",
+    "$source_root/include/inja/function_storage.hpp",
+    "$source_root/include/inja/inja.hpp",
+    "$source_root/include/inja/lexer.hpp",
+    "$source_root/include/inja/node.hpp",
+    "$source_root/include/inja/parser.hpp",
+    "$source_root/include/inja/renderer.hpp",
+    "$source_root/include/inja/statistics.hpp",
+    "$source_root/include/inja/string_view.hpp",
+    "$source_root/include/inja/template.hpp",
+    "$source_root/include/inja/token.hpp",
+    "$source_root/include/inja/utils.hpp",
+  ]
+
+  public_deps = [ "//third_party/json" ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/json/BUILD.gn b/engine/src/flutter/build/secondary/third_party/json/BUILD.gn
new file mode 100644
index 00000000000..bf24ebf1193
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/json/BUILD.gn
@@ -0,0 +1,63 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+source_root = "//third_party/json"
+
+config("json_public_config") {
+  include_dirs = [ "$source_root/include" ]
+}
+
+source_set("json") {
+  public_configs = [ ":json_public_config" ]
+
+  public = [ "$source_root/include/nlohmann/json.hpp" ]
+
+  sources = [
+    "$source_root/include/nlohmann/adl_serializer.hpp",
+    "$source_root/include/nlohmann/byte_container_with_subtype.hpp",
+    "$source_root/include/nlohmann/detail/abi_macros.hpp",
+    "$source_root/include/nlohmann/detail/conversions/from_json.hpp",
+    "$source_root/include/nlohmann/detail/conversions/to_chars.hpp",
+    "$source_root/include/nlohmann/detail/conversions/to_json.hpp",
+    "$source_root/include/nlohmann/detail/exceptions.hpp",
+    "$source_root/include/nlohmann/detail/hash.hpp",
+    "$source_root/include/nlohmann/detail/input/binary_reader.hpp",
+    "$source_root/include/nlohmann/detail/input/input_adapters.hpp",
+    "$source_root/include/nlohmann/detail/input/json_sax.hpp",
+    "$source_root/include/nlohmann/detail/input/lexer.hpp",
+    "$source_root/include/nlohmann/detail/input/parser.hpp",
+    "$source_root/include/nlohmann/detail/input/position_t.hpp",
+    "$source_root/include/nlohmann/detail/iterators/internal_iterator.hpp",
+    "$source_root/include/nlohmann/detail/iterators/iter_impl.hpp",
+    "$source_root/include/nlohmann/detail/iterators/iteration_proxy.hpp",
+    "$source_root/include/nlohmann/detail/iterators/iterator_traits.hpp",
+    "$source_root/include/nlohmann/detail/iterators/json_reverse_iterator.hpp",
+    "$source_root/include/nlohmann/detail/iterators/primitive_iterator.hpp",
+    "$source_root/include/nlohmann/detail/json_custom_base_class.hpp",
+    "$source_root/include/nlohmann/detail/json_pointer.hpp",
+    "$source_root/include/nlohmann/detail/json_ref.hpp",
+    "$source_root/include/nlohmann/detail/macro_scope.hpp",
+    "$source_root/include/nlohmann/detail/macro_unscope.hpp",
+    "$source_root/include/nlohmann/detail/meta/call_std/begin.hpp",
+    "$source_root/include/nlohmann/detail/meta/call_std/end.hpp",
+    "$source_root/include/nlohmann/detail/meta/cpp_future.hpp",
+    "$source_root/include/nlohmann/detail/meta/detected.hpp",
+    "$source_root/include/nlohmann/detail/meta/identity_tag.hpp",
+    "$source_root/include/nlohmann/detail/meta/is_sax.hpp",
+    "$source_root/include/nlohmann/detail/meta/std_fs.hpp",
+    "$source_root/include/nlohmann/detail/meta/type_traits.hpp",
+    "$source_root/include/nlohmann/detail/meta/void_t.hpp",
+    "$source_root/include/nlohmann/detail/output/binary_writer.hpp",
+    "$source_root/include/nlohmann/detail/output/output_adapters.hpp",
+    "$source_root/include/nlohmann/detail/output/serializer.hpp",
+    "$source_root/include/nlohmann/detail/string_concat.hpp",
+    "$source_root/include/nlohmann/detail/string_escape.hpp",
+    "$source_root/include/nlohmann/detail/value_t.hpp",
+    "$source_root/include/nlohmann/json.hpp",
+    "$source_root/include/nlohmann/json_fwd.hpp",
+    "$source_root/include/nlohmann/ordered_map.hpp",
+    "$source_root/include/nlohmann/thirdparty/hedley/hedley.hpp",
+    "$source_root/include/nlohmann/thirdparty/hedley/hedley_undef.hpp",
+  ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/jsoncpp/BUILD.gn b/engine/src/flutter/build/secondary/third_party/jsoncpp/BUILD.gn
new file mode 100644
index 00000000000..ff255b0add1
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/jsoncpp/BUILD.gn
@@ -0,0 +1,11 @@
+# Copyright 2019 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# The ANGLE build rules have a target that depends on jsoncpp, but the Flutter
+# engine never actually builds that target, so just this provides empty dummy
+# dependencies to satisfy the generation-time resolution.
+config("jsoncpp_config") {
+}
+group("jsoncpp") {
+}
diff --git a/engine/src/flutter/build/secondary/third_party/libcxx/BUILD.gn b/engine/src/flutter/build/secondary/third_party/libcxx/BUILD.gn
new file mode 100644
index 00000000000..710ebe465d1
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/libcxx/BUILD.gn
@@ -0,0 +1,117 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+config("libcxx_config") {
+  defines = [ "_LIBCPP_DISABLE_AVAILABILITY=1" ]
+  include_dirs = [ "//flutter/build/secondary/third_party/libcxx/config" ]
+}
+
+config("src_include") {
+  include_dirs = [ "src" ]
+}
+
+source_set("libcxx") {
+  sources = [
+    "src/algorithm.cpp",
+    "src/any.cpp",
+    "src/bind.cpp",
+    "src/charconv.cpp",
+    "src/chrono.cpp",
+    "src/condition_variable.cpp",
+    "src/condition_variable_destructor.cpp",
+    "src/debug.cpp",
+    "src/exception.cpp",
+    "src/filesystem/directory_iterator.cpp",
+    "src/filesystem/filesystem_common.h",
+    "src/filesystem/int128_builtins.cpp",
+    "src/filesystem/operations.cpp",
+    "src/functional.cpp",
+    "src/future.cpp",
+    "src/hash.cpp",
+    "src/ios.cpp",
+    "src/ios.instantiations.cpp",
+    "src/iostream.cpp",
+    "src/locale.cpp",
+    "src/memory.cpp",
+    "src/mutex.cpp",
+    "src/mutex_destructor.cpp",
+    "src/new.cpp",
+    "src/optional.cpp",
+    "src/random.cpp",
+    "src/regex.cpp",
+    "src/ryu/d2fixed.cpp",
+    "src/ryu/d2s.cpp",
+    "src/ryu/f2s.cpp",
+    "src/shared_mutex.cpp",
+    "src/stdexcept.cpp",
+    "src/string.cpp",
+    "src/strstream.cpp",
+    "src/system_error.cpp",
+    "src/thread.cpp",
+    "src/typeinfo.cpp",
+    "src/utility.cpp",
+    "src/valarray.cpp",
+    "src/variant.cpp",
+    "src/vector.cpp",
+  ]
+
+  deps = [ "//third_party/libcxxabi" ]
+
+  # TODO(goderbauer): remove when all sources build with LTO for android_arm64 and android_x64.
+  if (is_android && (current_cpu == "arm64" || current_cpu == "x64")) {
+    sources -= [ "src/new.cpp" ]
+    deps += [ ":libcxx_nolto" ]
+  }
+
+  public_configs = [
+    ":libcxx_config",
+    "//third_party/libcxxabi:libcxxabi_config",
+  ]
+
+  defines = [
+    "_LIBCPP_NO_EXCEPTIONS",
+    "_LIBCPP_NO_RTTI",
+    "_LIBCPP_BUILDING_LIBRARY",
+    "LIBCXX_BUILDING_LIBCXXABI",
+  ]
+
+  # While no translation units in Flutter engine enable RTTI, it may be enabled
+  # in one of the third party dependencies. This mirrors the configuration in
+  # libcxxabi.
+  configs -= [ "//build/config/compiler:no_rtti" ]
+  configs += [ "//build/config/compiler:rtti" ]
+
+  # libcxx requires C++20
+  configs -= [ "//build/config/compiler:cxx_version_default" ]
+  configs += [ "//build/config/compiler:cxx_version_20" ]
+
+  configs += [ ":src_include" ]
+
+  if (is_clang) {
+    # shared_mutex.cpp and debug.cpp are purposefully in violation.
+    cflags_cc = [ "-Wno-thread-safety-analysis" ]
+  }
+}
+
+source_set("libcxx_nolto") {
+  visibility = [ ":*" ]
+
+  sources = [ "src/new.cpp" ]
+
+  cflags_cc = [ "-fno-lto" ]
+
+  deps = [ "//third_party/libcxxabi" ]
+
+  public_configs = [
+    ":libcxx_config",
+    "//third_party/libcxxabi:libcxxabi_config",
+  ]
+
+  defines = [
+    "_LIBCPP_NO_EXCEPTIONS",
+    "_LIBCPP_NO_RTTI",
+    "_LIBCPP_BUILDING_LIBRARY",
+    "LIBCXX_BUILDING_LIBCXXABI",
+  ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/libcxx/config/__config_site b/engine/src/flutter/build/secondary/third_party/libcxx/config/__config_site
new file mode 100644
index 00000000000..106c24fc361
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/libcxx/config/__config_site
@@ -0,0 +1,39 @@
+#ifndef _LIBCPP_CONFIG_SITE
+#define _LIBCPP_CONFIG_SITE
+
+/* #undef _LIBCPP_ABI_VERSION */
+/* #undef _LIBCPP_ABI_UNSTABLE */
+/* #undef _LIBCPP_ABI_FORCE_ITANIUM */
+/* #undef _LIBCPP_ABI_FORCE_MICROSOFT */
+/* #undef _LIBCPP_HIDE_FROM_ABI_PER_TU_BY_DEFAULT */
+/* #undef _LIBCPP_HAS_NO_GLOBAL_FILESYSTEM_NAMESPACE */
+/* #undef _LIBCPP_HAS_NO_STDIN */
+/* #undef _LIBCPP_HAS_NO_STDOUT */
+/* #undef _LIBCPP_HAS_NO_THREADS */
+/* #undef _LIBCPP_HAS_NO_MONOTONIC_CLOCK */
+/* #undef _LIBCPP_HAS_NO_THREAD_UNSAFE_C_FUNCTIONS */
+/* #undef _LIBCPP_HAS_MUSL_LIBC */
+/* #undef _LIBCPP_HAS_THREAD_API_PTHREAD */
+/* #undef _LIBCPP_HAS_THREAD_API_EXTERNAL */
+/* #undef _LIBCPP_HAS_THREAD_API_WIN32 */
+/* #undef _LIBCPP_HAS_THREAD_LIBRARY_EXTERNAL */
+/* #undef _LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS */
+#define _LIBCPP_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS
+/* #undef _LIBCPP_NO_VCRUNTIME */
+/* #undef _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION */
+/* #undef _LIBCPP_ABI_NAMESPACE */
+/* #undef _LIBCPP_HAS_NO_FILESYSTEM_LIBRARY */
+/* #undef _LIBCPP_HAS_PARALLEL_ALGORITHMS */
+/* #undef _LIBCPP_HAS_NO_RANDOM_DEVICE */
+/* #undef _LIBCPP_HAS_NO_LOCALIZATION */
+
+#define _LIBCPP_REMOVE_TRANSITIVE_INCLUDES
+
+// This is a workaround for BoringSSL, which is compiled in C11 mode
+// and includes stdatomic.h.  Defining this macro will cause stdatomic.h
+// to redirect to the next version of that header in the include path.
+#if !defined(__cplusplus) && defined(__clang__)
+#define _LIBCPP_COMPILER_CLANG_BASED
+#endif
+
+#endif // _LIBCPP_CONFIG_SITE
diff --git a/engine/src/flutter/build/secondary/third_party/libcxxabi/BUILD.gn b/engine/src/flutter/build/secondary/third_party/libcxxabi/BUILD.gn
new file mode 100644
index 00000000000..10e51e78ac8
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/libcxxabi/BUILD.gn
@@ -0,0 +1,82 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+config("libcxxabi_config") {
+  common_cc_flags = [
+    "-nostdinc++",
+    "-fvisibility=hidden",
+  ]
+
+  cflags_cc = common_cc_flags
+  cflags_objcc = common_cc_flags
+
+  include_dirs = [ "include" ]
+
+  if (is_ios) {
+    ldflags = [ "-Wl,-unexported_symbols_list," +
+                rebase_path("lib/new-delete.exp", root_build_dir) ]
+  }
+}
+
+source_set("libcxxabi") {
+  visibility = [ "../libcxx:*" ]
+
+  public_configs = [ ":libcxxabi_config" ]
+
+  defines = [
+    "_LIBCPP_BUILDING_LIBRARY",
+    "_LIBCXXABI_BUILDING_LIBRARY",
+    "LIBCXXABI_SILENT_TERMINATE",
+    "_LIBCXXABI_DISABLE_VISIBILITY_ANNOTATIONS",
+  ]
+
+  sources = []
+
+  # Compile libcxx ABI using C++11. This replicates the rule in the
+  # CMakeLists on the "cxx_abiobjects" target.
+  configs -= [ "//build/config/compiler:cxx_version_default" ]
+  configs += [ "//build/config/compiler:cxx_version_20" ]
+
+  configs += [ "//third_party/libcxx:src_include" ]
+
+  # No translation units in the engine are built with exceptions. But, using
+  # Objective-C exceptions requires some infrastructure setup for exceptions.
+  # Build support for the same in cxxabi on Darwin.
+  if (is_mac || is_ios) {
+    configs -= [ "//build/config/gcc:no_exceptions" ]
+    sources += [
+      "src/cxa_exception.cpp",
+      "src/cxa_personality.cpp",
+    ]
+  } else {
+    if (!is_tsan) {
+      sources += [ "src/cxa_noexception.cpp" ]
+    }
+  }
+
+  # Third party dependencies may depend on RTTI. Add support for the same in
+  # cxxabi.
+  configs -= [ "//build/config/compiler:no_rtti" ]
+  configs += [ "//build/config/compiler:rtti" ]
+
+  sources += [
+    "src/abort_message.cpp",
+    "src/cxa_aux_runtime.cpp",
+    "src/cxa_default_handlers.cpp",
+    "src/cxa_demangle.cpp",
+    "src/cxa_exception_storage.cpp",
+    "src/cxa_handlers.cpp",
+    "src/cxa_vector.cpp",
+    "src/cxa_virtual.cpp",
+    "src/fallback_malloc.cpp",
+    "src/private_typeinfo.cpp",
+    "src/stdlib_exception.cpp",
+    "src/stdlib_stdexcept.cpp",
+    "src/stdlib_typeinfo.cpp",
+  ]
+
+  if (!(is_tsan && is_linux)) {
+    sources += [ "src/cxa_guard.cpp" ]
+  }
+}
diff --git a/engine/src/flutter/build/secondary/third_party/libjpeg-turbo/BUILD.gn b/engine/src/flutter/build/secondary/third_party/libjpeg-turbo/BUILD.gn
new file mode 100644
index 00000000000..55f346e49c8
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/libjpeg-turbo/BUILD.gn
@@ -0,0 +1,81 @@
+# Copyright 2016 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+config("libjpeg_config") {
+  include_dirs = [ "." ]
+}
+
+source_set("libjpeg") {
+  public_configs = [ ":libjpeg_config" ]
+
+  defines = []
+
+  if (!is_win) {
+    cflags_c = [
+      "-Wno-unused-variable",
+      "-Wno-unused-function",
+    ]
+  } else {
+    defines += [ "TURBO_FOR_WINDOWS" ]
+  }
+
+  sources = [
+    "//third_party/libjpeg-turbo/jcapimin.c",
+    "//third_party/libjpeg-turbo/jcapistd.c",
+    "//third_party/libjpeg-turbo/jccoefct.c",
+    "//third_party/libjpeg-turbo/jccolor.c",
+    "//third_party/libjpeg-turbo/jcdctmgr.c",
+    "//third_party/libjpeg-turbo/jchuff.c",
+    "//third_party/libjpeg-turbo/jcinit.c",
+    "//third_party/libjpeg-turbo/jcmainct.c",
+    "//third_party/libjpeg-turbo/jcmarker.c",
+    "//third_party/libjpeg-turbo/jcmaster.c",
+    "//third_party/libjpeg-turbo/jcomapi.c",
+    "//third_party/libjpeg-turbo/jcparam.c",
+    "//third_party/libjpeg-turbo/jcphuff.c",
+    "//third_party/libjpeg-turbo/jcprepct.c",
+    "//third_party/libjpeg-turbo/jcsample.c",
+    "//third_party/libjpeg-turbo/jdapimin.c",
+    "//third_party/libjpeg-turbo/jdapistd.c",
+    "//third_party/libjpeg-turbo/jdcoefct.c",
+    "//third_party/libjpeg-turbo/jdcolor.c",
+    "//third_party/libjpeg-turbo/jddctmgr.c",
+    "//third_party/libjpeg-turbo/jdhuff.c",
+    "//third_party/libjpeg-turbo/jdinput.c",
+    "//third_party/libjpeg-turbo/jdmainct.c",
+    "//third_party/libjpeg-turbo/jdmarker.c",
+    "//third_party/libjpeg-turbo/jdmaster.c",
+    "//third_party/libjpeg-turbo/jdmerge.c",
+    "//third_party/libjpeg-turbo/jdphuff.c",
+    "//third_party/libjpeg-turbo/jdpostct.c",
+    "//third_party/libjpeg-turbo/jdsample.c",
+    "//third_party/libjpeg-turbo/jerror.c",
+    "//third_party/libjpeg-turbo/jfdctflt.c",
+    "//third_party/libjpeg-turbo/jfdctfst.c",
+    "//third_party/libjpeg-turbo/jfdctint.c",
+    "//third_party/libjpeg-turbo/jidctflt.c",
+    "//third_party/libjpeg-turbo/jidctfst.c",
+    "//third_party/libjpeg-turbo/jidctint.c",
+    "//third_party/libjpeg-turbo/jidctred.c",
+    "//third_party/libjpeg-turbo/jmemmgr.c",
+    "//third_party/libjpeg-turbo/jmemnobs.c",
+    "//third_party/libjpeg-turbo/jquant1.c",
+    "//third_party/libjpeg-turbo/jquant2.c",
+    "//third_party/libjpeg-turbo/jutils.c",
+  ]
+
+  if (current_cpu == "arm" && !is_ios) {
+    sources += [
+      "//third_party/libjpeg-turbo/simd/jsimd_arm.c",
+      "//third_party/libjpeg-turbo/simd/jsimd_arm_neon.S",
+    ]
+  } else if (current_cpu == "arm64") {
+    sources += [
+      "//third_party/libjpeg-turbo/simd/jsimd_arm64.c",
+      "//third_party/libjpeg-turbo/simd/jsimd_arm64_neon.S",
+    ]
+  } else {
+    sources += [ "//third_party/libjpeg-turbo/jsimd_none.c" ]
+  }
+}
diff --git a/engine/src/flutter/build/secondary/third_party/libsrtp/BUILD.gn b/engine/src/flutter/build/secondary/third_party/libsrtp/BUILD.gn
new file mode 100644
index 00000000000..5697e3175f0
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/libsrtp/BUILD.gn
@@ -0,0 +1,345 @@
+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+declare_args() {
+  use_system_libsrtp = false
+  use_srtp_boringssl = true
+}
+
+config("libsrtp_config") {
+  defines = [
+    "HAVE_CONFIG_H",
+    "HAVE_STDLIB_H",
+    "HAVE_STRING_H",
+    "TESTAPP_SOURCE",
+  ]
+
+  include_dirs = [
+    "config",
+    "srtp/include",
+    "srtp/crypto/include",
+  ]
+
+  if (use_srtp_boringssl) {
+    defines += [ "OPENSSL" ]
+  }
+
+  if (is_posix) {
+    defines += [
+      "HAVE_INT16_T",
+      "HAVE_INT32_T",
+      "HAVE_INT8_T",
+      "HAVE_UINT16_T",
+      "HAVE_UINT32_T",
+      "HAVE_UINT64_T",
+      "HAVE_UINT8_T",
+      "HAVE_STDINT_H",
+      "HAVE_INTTYPES_H",
+      "HAVE_NETINET_IN_H",
+      "HAVE_ARPA_INET_H",
+      "HAVE_UNISTD_H",
+    ]
+    cflags = [ "-Wno-unused-variable" ]
+  }
+
+  if (is_win) {
+    defines += [
+      "HAVE_BYTESWAP_METHODS_H",
+
+      # All Windows architectures are this way.
+      "SIZEOF_UNSIGNED_LONG=4",
+      "SIZEOF_UNSIGNED_LONG_LONG=8",
+    ]
+  }
+
+  if (current_cpu == "x64" || current_cpu == "x86" || current_cpu == "arm") {
+    defines += [
+      # TODO(leozwang): CPU_RISC doesn"t work properly on android/arm
+      # platform for unknown reasons, need to investigate the root cause
+      # of it. CPU_RISC is used for optimization only, and CPU_CISC should
+      # just work just fine, it has been tested on android/arm with srtp
+      # test applications and libjingle.
+      "CPU_CISC",
+    ]
+  }
+}
+
+config("system_libsrtp_config") {
+  defines = [ "USE_SYSTEM_LIBSRTP" ]
+  include_dirs = [ "/usr/include/srtp" ]
+}
+
+if (use_system_libsrtp) {
+  group("libsrtp") {
+    public_configs = [
+      ":libsrtp_config",
+      ":system_libsrtp_config",
+    ]
+    libs = [ "-lsrtp" ]
+  }
+} else {
+  static_library("libsrtp") {
+    configs -= [ "//build/config/compiler:chromium_code" ]
+    configs += [ "//build/config/compiler:no_chromium_code" ]
+    public_configs = [ ":libsrtp_config" ]
+
+    sources = [
+      # includes
+      "srtp/include/ekt.h",
+      "srtp/include/getopt_s.h",
+      "srtp/include/rtp.h",
+      "srtp/include/rtp_priv.h",
+      "srtp/include/srtp.h",
+      "srtp/include/srtp_priv.h",
+      "srtp/include/ut_sim.h",
+
+      # headers
+      "srtp/crypto/include/aes.h",
+      "srtp/crypto/include/aes_cbc.h",
+      "srtp/crypto/include/aes_icm.h",
+      "srtp/crypto/include/alloc.h",
+      "srtp/crypto/include/auth.h",
+      "srtp/crypto/include/cipher.h",
+      "srtp/crypto/include/crypto.h",
+      "srtp/crypto/include/crypto_kernel.h",
+      "srtp/crypto/include/crypto_math.h",
+      "srtp/crypto/include/crypto_types.h",
+      "srtp/crypto/include/cryptoalg.h",
+      "srtp/crypto/include/datatypes.h",
+      "srtp/crypto/include/err.h",
+      "srtp/crypto/include/gf2_8.h",
+      "srtp/crypto/include/hmac.h",
+      "srtp/crypto/include/integers.h",
+      "srtp/crypto/include/kernel_compat.h",
+      "srtp/crypto/include/key.h",
+      "srtp/crypto/include/null_auth.h",
+      "srtp/crypto/include/null_cipher.h",
+      "srtp/crypto/include/prng.h",
+      "srtp/crypto/include/rand_source.h",
+      "srtp/crypto/include/rdb.h",
+      "srtp/crypto/include/rdbx.h",
+      "srtp/crypto/include/sha1.h",
+      "srtp/crypto/include/stat.h",
+      "srtp/crypto/include/xfm.h",
+
+      # sources
+      "srtp/crypto/cipher/aes.c",
+      "srtp/crypto/cipher/aes_cbc.c",
+      "srtp/crypto/cipher/aes_icm.c",
+      "srtp/crypto/cipher/cipher.c",
+      "srtp/crypto/cipher/null_cipher.c",
+      "srtp/crypto/hash/auth.c",
+      "srtp/crypto/hash/hmac.c",
+      "srtp/crypto/hash/null_auth.c",
+      "srtp/crypto/hash/sha1.c",
+      "srtp/crypto/kernel/alloc.c",
+      "srtp/crypto/kernel/crypto_kernel.c",
+      "srtp/crypto/kernel/err.c",
+      "srtp/crypto/kernel/key.c",
+      "srtp/crypto/math/datatypes.c",
+      "srtp/crypto/math/gf2_8.c",
+      "srtp/crypto/math/stat.c",
+      "srtp/crypto/replay/rdb.c",
+      "srtp/crypto/replay/rdbx.c",
+      "srtp/crypto/replay/ut_sim.c",
+      "srtp/crypto/rng/ctr_prng.c",
+      "srtp/crypto/rng/prng.c",
+      "srtp/crypto/rng/rand_source.c",
+      "srtp/srtp/ekt.c",
+      "srtp/srtp/srtp.c",
+    ]
+
+    if (is_clang) {
+      cflags = [ "-Wno-implicit-function-declaration" ]
+    }
+
+    if (use_srtp_boringssl) {
+      deps = [ "//third_party/boringssl:boringssl" ]
+      public_deps = [ "//third_party/boringssl:boringssl" ]
+      sources -= [
+        "srtp/crypto/cipher/aes_cbc.c",
+        "srtp/crypto/cipher/aes_icm.c",
+        "srtp/crypto/hash/hmac.c",
+        "srtp/crypto/hash/sha1.c",
+        "srtp/crypto/rng/ctr_prng.c",
+        "srtp/crypto/rng/prng.c",
+      ]
+      sources += [
+        "srtp/crypto/cipher/aes_gcm_ossl.c",
+        "srtp/crypto/cipher/aes_icm_ossl.c",
+        "srtp/crypto/hash/hmac_ossl.c",
+        "srtp/crypto/include/aes_gcm_ossl.h",
+        "srtp/crypto/include/aes_icm_ossl.h",
+      ]
+    }
+  }
+
+  # TODO(GYP): A bunch of these tests don't compile (in gyp either). They're
+  # not very broken, so could probably be made to work if it's useful.
+  if (!is_win) {
+    executable("rdbx_driver") {
+      configs -= [ "//build/config/compiler:chromium_code" ]
+      configs += [ "//build/config/compiler:no_chromium_code" ]
+      deps = [ ":libsrtp" ]
+      sources = [
+        "srtp/include/getopt_s.h",
+        "srtp/test/getopt_s.c",
+        "srtp/test/rdbx_driver.c",
+      ]
+    }
+
+    executable("srtp_driver") {
+      configs -= [ "//build/config/compiler:chromium_code" ]
+      configs += [ "//build/config/compiler:no_chromium_code" ]
+      deps = [ ":libsrtp" ]
+      sources = [
+        "srtp/include/getopt_s.h",
+        "srtp/include/srtp_priv.h",
+        "srtp/test/getopt_s.c",
+        "srtp/test/srtp_driver.c",
+      ]
+    }
+
+    executable("roc_driver") {
+      configs -= [ "//build/config/compiler:chromium_code" ]
+      configs += [ "//build/config/compiler:no_chromium_code" ]
+      deps = [ ":libsrtp" ]
+      sources = [
+        "srtp/crypto/include/rdbx.h",
+        "srtp/include/ut_sim.h",
+        "srtp/test/roc_driver.c",
+      ]
+    }
+
+    executable("replay_driver") {
+      configs -= [ "//build/config/compiler:chromium_code" ]
+      configs += [ "//build/config/compiler:no_chromium_code" ]
+      deps = [ ":libsrtp" ]
+      sources = [
+        "srtp/crypto/include/rdbx.h",
+        "srtp/include/ut_sim.h",
+        "srtp/test/replay_driver.c",
+      ]
+    }
+
+    executable("rtpw") {
+      configs -= [ "//build/config/compiler:chromium_code" ]
+      configs += [ "//build/config/compiler:no_chromium_code" ]
+      deps = [ ":libsrtp" ]
+      sources = [
+        "srtp/crypto/include/datatypes.h",
+        "srtp/include/getopt_s.h",
+        "srtp/include/rtp.h",
+        "srtp/include/srtp.h",
+        "srtp/test/getopt_s.c",
+        "srtp/test/rtp.c",
+        "srtp/test/rtpw.c",
+      ]
+      if (is_android) {
+        defines = [ "HAVE_SYS_SOCKET_H" ]
+      }
+      if (is_clang) {
+        cflags = [ "-Wno-implicit-function-declaration" ]
+      }
+    }
+
+    executable("srtp_test_cipher_driver") {
+      configs -= [ "//build/config/compiler:chromium_code" ]
+      configs += [ "//build/config/compiler:no_chromium_code" ]
+      deps = [ ":libsrtp" ]
+      sources = [
+        "srtp/crypto/test/cipher_driver.c",
+        "srtp/include/getopt_s.h",
+        "srtp/test/getopt_s.c",
+      ]
+    }
+
+    executable("srtp_test_datatypes_driver") {
+      configs -= [ "//build/config/compiler:chromium_code" ]
+      configs += [ "//build/config/compiler:no_chromium_code" ]
+      deps = [ ":libsrtp" ]
+      sources = [ "srtp/crypto/test/datatypes_driver.c" ]
+    }
+
+    executable("srtp_test_stat_driver") {
+      configs -= [ "//build/config/compiler:chromium_code" ]
+      configs += [ "//build/config/compiler:no_chromium_code" ]
+      deps = [ ":libsrtp" ]
+      sources = [ "srtp/crypto/test/stat_driver.c" ]
+    }
+
+    executable("srtp_test_sha1_driver") {
+      configs -= [ "//build/config/compiler:chromium_code" ]
+      configs += [ "//build/config/compiler:no_chromium_code" ]
+      deps = [ ":libsrtp" ]
+      sources = [ "srtp/crypto/test/sha1_driver.c" ]
+    }
+
+    executable("srtp_test_kernel_driver") {
+      configs -= [ "//build/config/compiler:chromium_code" ]
+      configs += [ "//build/config/compiler:no_chromium_code" ]
+      deps = [ ":libsrtp" ]
+      sources = [
+        "srtp/crypto/test/kernel_driver.c",
+        "srtp/include/getopt_s.h",
+        "srtp/test/getopt_s.c",
+      ]
+    }
+
+    executable("srtp_test_aes_calc") {
+      configs -= [ "//build/config/compiler:chromium_code" ]
+      configs += [ "//build/config/compiler:no_chromium_code" ]
+      deps = [ ":libsrtp" ]
+      sources = [ "srtp/crypto/test/aes_calc.c" ]
+    }
+
+    executable("srtp_test_rand_gen") {
+      configs -= [ "//build/config/compiler:chromium_code" ]
+      configs += [ "//build/config/compiler:no_chromium_code" ]
+      deps = [ ":libsrtp" ]
+      sources = [
+        "srtp/crypto/test/rand_gen.c",
+        "srtp/include/getopt_s.h",
+        "srtp/test/getopt_s.c",
+      ]
+    }
+
+    executable("srtp_test_rand_gen_soak") {
+      configs -= [ "//build/config/compiler:chromium_code" ]
+      configs += [ "//build/config/compiler:no_chromium_code" ]
+      deps = [ ":libsrtp" ]
+      sources = [
+        "srtp/crypto/test/rand_gen_soak.c",
+        "srtp/include/getopt_s.h",
+        "srtp/test/getopt_s.c",
+      ]
+    }
+
+    executable("srtp_test_env") {
+      configs -= [ "//build/config/compiler:chromium_code" ]
+      configs += [ "//build/config/compiler:no_chromium_code" ]
+      deps = [ ":libsrtp" ]
+      sources = [ "srtp/crypto/test/env.c" ]
+    }
+
+    group("srtp_runtest") {
+      deps = [
+        ":rdbx_driver",
+        ":replay_driver",
+        ":roc_driver",
+        ":rtpw",
+        ":srtp_driver",
+        ":srtp_test_aes_calc",
+        ":srtp_test_cipher_driver",
+        ":srtp_test_datatypes_driver",
+        ":srtp_test_env",
+        ":srtp_test_kernel_driver",
+        ":srtp_test_rand_gen",
+        ":srtp_test_rand_gen_soak",
+        ":srtp_test_sha1_driver",
+        ":srtp_test_stat_driver",
+      ]
+    }
+  }
+}
diff --git a/engine/src/flutter/build/secondary/third_party/libtess2/BUILD.gn b/engine/src/flutter/build/secondary/third_party/libtess2/BUILD.gn
new file mode 100644
index 00000000000..4d9ac96f8b0
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/libtess2/BUILD.gn
@@ -0,0 +1,29 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+source_set("libtess2") {
+  public = [ "//third_party/libtess2/Include/tesselator.h" ]
+
+  include_dirs = [ "//third_party/libtess2/Include/" ]
+
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
+
+  sources = [
+    "//third_party/libtess2/Source/bucketalloc.c",
+    "//third_party/libtess2/Source/bucketalloc.h",
+    "//third_party/libtess2/Source/dict.c",
+    "//third_party/libtess2/Source/dict.h",
+    "//third_party/libtess2/Source/geom.c",
+    "//third_party/libtess2/Source/geom.h",
+    "//third_party/libtess2/Source/mesh.c",
+    "//third_party/libtess2/Source/mesh.h",
+    "//third_party/libtess2/Source/priorityq.c",
+    "//third_party/libtess2/Source/priorityq.h",
+    "//third_party/libtess2/Source/sweep.c",
+    "//third_party/libtess2/Source/sweep.h",
+    "//third_party/libtess2/Source/tess.c",
+    "//third_party/libtess2/Source/tess.h",
+  ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/libwebp/BUILD.gn b/engine/src/flutter/build/secondary/third_party/libwebp/BUILD.gn
new file mode 100644
index 00000000000..4a251062234
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/libwebp/BUILD.gn
@@ -0,0 +1,178 @@
+# Copyright 2017 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# This file is based on:
+# https://skia.googlesource.com/skia/+/main/third_party/libwebp/BUILD.gn
+config("libwebp_config") {
+  include_dirs = [
+    "//third_party/libwebp/src",
+    "//third_party/libwebp",
+  ]
+}
+
+config("libwebp_defines") {
+  defines = [
+    # WebP naturally decodes to RGB_565, Skia with BGR_565.
+    # This makes WebP decode to BGR_565 when we ask for RGB_565.
+    # (It also swaps the color order for 4444, but we don't care today.)
+    "WEBP_SWAP_16BIT_CSP",
+
+    # Prevent WebP symbols from being exposed.
+    "WEBP_EXTERN=extern",
+  ]
+}
+
+source_set("libwebp_sse41") {
+  include_dirs = [
+    "//third_party/libwebp/src",
+    "//third_party/libwebp",
+  ]
+  configs += [ ":libwebp_defines" ]
+  sources = [
+    "//third_party/libwebp/src/dsp/alpha_processing_sse41.c",
+    "//third_party/libwebp/src/dsp/dec_sse41.c",
+    "//third_party/libwebp/src/dsp/enc_sse41.c",
+    "//third_party/libwebp/src/dsp/lossless_enc_sse41.c",
+    "//third_party/libwebp/src/dsp/lossless_sse41.c",
+    "//third_party/libwebp/src/dsp/upsampling_sse41.c",
+    "//third_party/libwebp/src/dsp/yuv_sse41.c",
+  ]
+  if ((current_cpu == "x86" || current_cpu == "x64") && (!is_win || is_clang)) {
+    cflags_c = [ "-msse4.1" ]
+  }
+}
+
+source_set("libwebp") {
+  public_configs = [ ":libwebp_config" ]
+  include_dirs = [
+    "//third_party/libwebp/src",
+    "//third_party/libwebp",
+  ]
+
+  deps = [ ":libwebp_sse41" ]
+
+  if (is_android) {
+    deps += [ "//third_party/cpu-features" ]
+  }
+
+  configs += [ ":libwebp_defines" ]
+
+  sources = [
+    "//third_party/libwebp/sharpyuv/sharpyuv.c",
+    "//third_party/libwebp/sharpyuv/sharpyuv_cpu.c",
+    "//third_party/libwebp/sharpyuv/sharpyuv_csp.c",
+    "//third_party/libwebp/sharpyuv/sharpyuv_dsp.c",
+    "//third_party/libwebp/sharpyuv/sharpyuv_gamma.c",
+    "//third_party/libwebp/sharpyuv/sharpyuv_neon.c",
+    "//third_party/libwebp/sharpyuv/sharpyuv_sse2.c",
+    "//third_party/libwebp/src/dec/alpha_dec.c",
+    "//third_party/libwebp/src/dec/buffer_dec.c",
+    "//third_party/libwebp/src/dec/frame_dec.c",
+    "//third_party/libwebp/src/dec/idec_dec.c",
+    "//third_party/libwebp/src/dec/io_dec.c",
+    "//third_party/libwebp/src/dec/quant_dec.c",
+    "//third_party/libwebp/src/dec/tree_dec.c",
+    "//third_party/libwebp/src/dec/vp8_dec.c",
+    "//third_party/libwebp/src/dec/vp8l_dec.c",
+    "//third_party/libwebp/src/dec/webp_dec.c",
+    "//third_party/libwebp/src/demux/anim_decode.c",
+    "//third_party/libwebp/src/demux/demux.c",
+    "//third_party/libwebp/src/dsp/alpha_processing.c",
+    "//third_party/libwebp/src/dsp/alpha_processing_mips_dsp_r2.c",
+    "//third_party/libwebp/src/dsp/alpha_processing_neon.c",
+    "//third_party/libwebp/src/dsp/alpha_processing_sse2.c",
+    "//third_party/libwebp/src/dsp/cost.c",
+    "//third_party/libwebp/src/dsp/cost_mips32.c",
+    "//third_party/libwebp/src/dsp/cost_mips_dsp_r2.c",
+    "//third_party/libwebp/src/dsp/cost_neon.c",
+    "//third_party/libwebp/src/dsp/cost_sse2.c",
+    "//third_party/libwebp/src/dsp/cpu.c",
+    "//third_party/libwebp/src/dsp/dec.c",
+    "//third_party/libwebp/src/dsp/dec_clip_tables.c",
+    "//third_party/libwebp/src/dsp/dec_mips32.c",
+    "//third_party/libwebp/src/dsp/dec_mips_dsp_r2.c",
+    "//third_party/libwebp/src/dsp/dec_msa.c",
+    "//third_party/libwebp/src/dsp/dec_neon.c",
+    "//third_party/libwebp/src/dsp/dec_sse2.c",
+    "//third_party/libwebp/src/dsp/enc.c",
+    "//third_party/libwebp/src/dsp/enc_mips32.c",
+    "//third_party/libwebp/src/dsp/enc_mips_dsp_r2.c",
+    "//third_party/libwebp/src/dsp/enc_msa.c",
+    "//third_party/libwebp/src/dsp/enc_neon.c",
+    "//third_party/libwebp/src/dsp/enc_sse2.c",
+    "//third_party/libwebp/src/dsp/filters.c",
+    "//third_party/libwebp/src/dsp/filters_mips_dsp_r2.c",
+    "//third_party/libwebp/src/dsp/filters_msa.c",
+    "//third_party/libwebp/src/dsp/filters_neon.c",
+    "//third_party/libwebp/src/dsp/filters_sse2.c",
+    "//third_party/libwebp/src/dsp/lossless.c",
+    "//third_party/libwebp/src/dsp/lossless_enc.c",
+    "//third_party/libwebp/src/dsp/lossless_enc_mips32.c",
+    "//third_party/libwebp/src/dsp/lossless_enc_mips_dsp_r2.c",
+    "//third_party/libwebp/src/dsp/lossless_enc_msa.c",
+    "//third_party/libwebp/src/dsp/lossless_enc_neon.c",
+    "//third_party/libwebp/src/dsp/lossless_enc_sse2.c",
+    "//third_party/libwebp/src/dsp/lossless_mips_dsp_r2.c",
+    "//third_party/libwebp/src/dsp/lossless_msa.c",
+    "//third_party/libwebp/src/dsp/lossless_neon.c",
+    "//third_party/libwebp/src/dsp/lossless_sse2.c",
+    "//third_party/libwebp/src/dsp/rescaler.c",
+    "//third_party/libwebp/src/dsp/rescaler_mips32.c",
+    "//third_party/libwebp/src/dsp/rescaler_mips_dsp_r2.c",
+    "//third_party/libwebp/src/dsp/rescaler_msa.c",
+    "//third_party/libwebp/src/dsp/rescaler_neon.c",
+    "//third_party/libwebp/src/dsp/rescaler_sse2.c",
+    "//third_party/libwebp/src/dsp/ssim.c",
+    "//third_party/libwebp/src/dsp/ssim_sse2.c",
+    "//third_party/libwebp/src/dsp/upsampling.c",
+    "//third_party/libwebp/src/dsp/upsampling_mips_dsp_r2.c",
+    "//third_party/libwebp/src/dsp/upsampling_msa.c",
+    "//third_party/libwebp/src/dsp/upsampling_neon.c",
+    "//third_party/libwebp/src/dsp/upsampling_sse2.c",
+    "//third_party/libwebp/src/dsp/yuv.c",
+    "//third_party/libwebp/src/dsp/yuv_mips32.c",
+    "//third_party/libwebp/src/dsp/yuv_mips_dsp_r2.c",
+    "//third_party/libwebp/src/dsp/yuv_neon.c",
+    "//third_party/libwebp/src/dsp/yuv_sse2.c",
+    "//third_party/libwebp/src/enc/alpha_enc.c",
+    "//third_party/libwebp/src/enc/analysis_enc.c",
+    "//third_party/libwebp/src/enc/backward_references_cost_enc.c",
+    "//third_party/libwebp/src/enc/backward_references_enc.c",
+    "//third_party/libwebp/src/enc/config_enc.c",
+    "//third_party/libwebp/src/enc/cost_enc.c",
+    "//third_party/libwebp/src/enc/filter_enc.c",
+    "//third_party/libwebp/src/enc/frame_enc.c",
+    "//third_party/libwebp/src/enc/histogram_enc.c",
+    "//third_party/libwebp/src/enc/iterator_enc.c",
+    "//third_party/libwebp/src/enc/near_lossless_enc.c",
+    "//third_party/libwebp/src/enc/picture_csp_enc.c",
+    "//third_party/libwebp/src/enc/picture_enc.c",
+    "//third_party/libwebp/src/enc/picture_psnr_enc.c",
+    "//third_party/libwebp/src/enc/picture_rescale_enc.c",
+    "//third_party/libwebp/src/enc/picture_tools_enc.c",
+    "//third_party/libwebp/src/enc/predictor_enc.c",
+    "//third_party/libwebp/src/enc/quant_enc.c",
+    "//third_party/libwebp/src/enc/syntax_enc.c",
+    "//third_party/libwebp/src/enc/token_enc.c",
+    "//third_party/libwebp/src/enc/tree_enc.c",
+    "//third_party/libwebp/src/enc/vp8l_enc.c",
+    "//third_party/libwebp/src/enc/webp_enc.c",
+    "//third_party/libwebp/src/mux/anim_encode.c",
+    "//third_party/libwebp/src/mux/muxedit.c",
+    "//third_party/libwebp/src/mux/muxinternal.c",
+    "//third_party/libwebp/src/mux/muxread.c",
+    "//third_party/libwebp/src/utils/bit_reader_utils.c",
+    "//third_party/libwebp/src/utils/bit_writer_utils.c",
+    "//third_party/libwebp/src/utils/color_cache_utils.c",
+    "//third_party/libwebp/src/utils/filters_utils.c",
+    "//third_party/libwebp/src/utils/huffman_encode_utils.c",
+    "//third_party/libwebp/src/utils/huffman_utils.c",
+    "//third_party/libwebp/src/utils/quant_levels_dec_utils.c",
+    "//third_party/libwebp/src/utils/quant_levels_utils.c",
+    "//third_party/libwebp/src/utils/random_utils.c",
+    "//third_party/libwebp/src/utils/rescaler_utils.c",
+    "//third_party/libwebp/src/utils/thread_utils.c",
+    "//third_party/libwebp/src/utils/utils.c",
+  ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/nss/BUILD.gn b/engine/src/flutter/build/secondary/third_party/nss/BUILD.gn
new file mode 100644
index 00000000000..95e6347c753
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/nss/BUILD.gn
@@ -0,0 +1,1205 @@
+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import("//build/config/linux/pkg_config.gni")
+
+if (is_linux) {
+  # This is a dependency on NSS with no libssl. On Linux we use a built-in SSL
+  # library but the system NSS libraries. Non-Linux platforms using NSS use the
+  # hermetic one in //third_party/nss.
+  #
+  # Generally you should depend on //crypto:platform instead of using this
+  # config since that will properly pick up NSS or OpenSSL depending on
+  # platform and build config.
+  pkg_config("system_nss_no_ssl_config") {
+    packages = [ "nss" ]
+    extra_args = [
+      "-v",
+      "-lssl3",
+    ]
+  }
+} else {
+  include_nss_root_certs = is_ios
+  include_nss_libpkix = is_ios
+
+  config("nspr_config") {
+    defines = [ "NO_NSPR_10_SUPPORT" ]
+    include_dirs = [
+      "nspr/pr/include",
+      "nspr/lib/ds",
+      "nspr/lib/libc/include",
+    ]
+
+    if (component_mode != "shared_library") {
+      defines += [ "NSPR_STATIC" ]
+    }
+  }
+
+  component("nspr") {
+    output_name = "crnspr"
+    sources = [
+      "nspr/lib/ds/plarena.c",
+      "nspr/lib/ds/plarena.h",
+      "nspr/lib/ds/plarenas.h",
+      "nspr/lib/ds/plhash.c",
+      "nspr/lib/ds/plhash.h",
+      "nspr/lib/libc/include/plbase64.h",
+      "nspr/lib/libc/include/plerror.h",
+      "nspr/lib/libc/include/plgetopt.h",
+      "nspr/lib/libc/include/plstr.h",
+      "nspr/lib/libc/src/base64.c",
+      "nspr/lib/libc/src/plerror.c",
+      "nspr/lib/libc/src/plgetopt.c",
+      "nspr/lib/libc/src/strcase.c",
+      "nspr/lib/libc/src/strcat.c",
+      "nspr/lib/libc/src/strchr.c",
+      "nspr/lib/libc/src/strcmp.c",
+      "nspr/lib/libc/src/strcpy.c",
+      "nspr/lib/libc/src/strdup.c",
+      "nspr/lib/libc/src/strlen.c",
+      "nspr/lib/libc/src/strpbrk.c",
+      "nspr/lib/libc/src/strstr.c",
+      "nspr/lib/libc/src/strtok.c",
+      "nspr/pr/include/md/_darwin.cfg",
+      "nspr/pr/include/md/_darwin.h",
+      "nspr/pr/include/md/_pcos.h",
+      "nspr/pr/include/md/_pth.h",
+      "nspr/pr/include/md/_unix_errors.h",
+      "nspr/pr/include/md/_unixos.h",
+      "nspr/pr/include/md/_win32_errors.h",
+      "nspr/pr/include/md/_win95.cfg",
+      "nspr/pr/include/md/_win95.h",
+      "nspr/pr/include/md/prosdep.h",
+      "nspr/pr/include/nspr.h",
+      "nspr/pr/include/obsolete/pralarm.h",
+      "nspr/pr/include/obsolete/probslet.h",
+      "nspr/pr/include/obsolete/protypes.h",
+      "nspr/pr/include/obsolete/prsem.h",
+      "nspr/pr/include/pratom.h",
+      "nspr/pr/include/prbit.h",
+      "nspr/pr/include/prclist.h",
+      "nspr/pr/include/prcmon.h",
+      "nspr/pr/include/prcountr.h",
+      "nspr/pr/include/prcpucfg.h",
+      "nspr/pr/include/prcvar.h",
+      "nspr/pr/include/prdtoa.h",
+      "nspr/pr/include/prenv.h",
+      "nspr/pr/include/prerr.h",
+      "nspr/pr/include/prerror.h",
+      "nspr/pr/include/prinet.h",
+      "nspr/pr/include/prinit.h",
+      "nspr/pr/include/prinrval.h",
+      "nspr/pr/include/prio.h",
+      "nspr/pr/include/pripcsem.h",
+      "nspr/pr/include/private/pprio.h",
+      "nspr/pr/include/private/pprmwait.h",
+      "nspr/pr/include/private/pprthred.h",
+      "nspr/pr/include/private/primpl.h",
+      "nspr/pr/include/private/prpriv.h",
+      "nspr/pr/include/prlink.h",
+      "nspr/pr/include/prlock.h",
+      "nspr/pr/include/prlog.h",
+      "nspr/pr/include/prlong.h",
+      "nspr/pr/include/prmem.h",
+      "nspr/pr/include/prmon.h",
+      "nspr/pr/include/prmwait.h",
+      "nspr/pr/include/prnetdb.h",
+      "nspr/pr/include/prolock.h",
+      "nspr/pr/include/prpdce.h",
+      "nspr/pr/include/prprf.h",
+      "nspr/pr/include/prproces.h",
+      "nspr/pr/include/prrng.h",
+      "nspr/pr/include/prrwlock.h",
+      "nspr/pr/include/prshm.h",
+      "nspr/pr/include/prshma.h",
+      "nspr/pr/include/prsystem.h",
+      "nspr/pr/include/prthread.h",
+      "nspr/pr/include/prtime.h",
+      "nspr/pr/include/prtpool.h",
+      "nspr/pr/include/prtrace.h",
+      "nspr/pr/include/prtypes.h",
+      "nspr/pr/include/prvrsion.h",
+      "nspr/pr/include/prwin16.h",
+      "nspr/pr/src/io/prdir.c",
+      "nspr/pr/src/io/prfdcach.c",
+      "nspr/pr/src/io/prfile.c",
+      "nspr/pr/src/io/prio.c",
+      "nspr/pr/src/io/priometh.c",
+      "nspr/pr/src/io/pripv6.c",
+      "nspr/pr/src/io/prlayer.c",
+      "nspr/pr/src/io/prlog.c",
+      "nspr/pr/src/io/prmapopt.c",
+      "nspr/pr/src/io/prmmap.c",
+      "nspr/pr/src/io/prmwait.c",
+      "nspr/pr/src/io/prpolevt.c",
+      "nspr/pr/src/io/prprf.c",
+      "nspr/pr/src/io/prscanf.c",
+      "nspr/pr/src/io/prsocket.c",
+      "nspr/pr/src/io/prstdio.c",
+      "nspr/pr/src/linking/prlink.c",
+      "nspr/pr/src/malloc/prmalloc.c",
+      "nspr/pr/src/malloc/prmem.c",
+      "nspr/pr/src/md/prosdep.c",
+      "nspr/pr/src/md/unix/darwin.c",
+      "nspr/pr/src/md/unix/os_Darwin.s",
+      "nspr/pr/src/md/unix/unix.c",
+      "nspr/pr/src/md/unix/unix_errors.c",
+      "nspr/pr/src/md/unix/uxproces.c",
+      "nspr/pr/src/md/unix/uxrng.c",
+      "nspr/pr/src/md/unix/uxshm.c",
+      "nspr/pr/src/md/unix/uxwrap.c",
+      "nspr/pr/src/md/windows/ntgc.c",
+      "nspr/pr/src/md/windows/ntinrval.c",
+      "nspr/pr/src/md/windows/ntmisc.c",
+      "nspr/pr/src/md/windows/ntsec.c",
+      "nspr/pr/src/md/windows/ntsem.c",
+      "nspr/pr/src/md/windows/w32ipcsem.c",
+      "nspr/pr/src/md/windows/w32poll.c",
+      "nspr/pr/src/md/windows/w32rng.c",
+      "nspr/pr/src/md/windows/w32shm.c",
+      "nspr/pr/src/md/windows/w95cv.c",
+      "nspr/pr/src/md/windows/w95dllmain.c",
+      "nspr/pr/src/md/windows/w95io.c",
+      "nspr/pr/src/md/windows/w95sock.c",
+      "nspr/pr/src/md/windows/w95thred.c",
+      "nspr/pr/src/md/windows/win32_errors.c",
+      "nspr/pr/src/memory/prseg.c",
+      "nspr/pr/src/memory/prshm.c",
+      "nspr/pr/src/memory/prshma.c",
+      "nspr/pr/src/misc/pralarm.c",
+      "nspr/pr/src/misc/pratom.c",
+      "nspr/pr/src/misc/praton.c",
+      "nspr/pr/src/misc/prcountr.c",
+      "nspr/pr/src/misc/prdtoa.c",
+      "nspr/pr/src/misc/prenv.c",
+      "nspr/pr/src/misc/prerr.c",
+      "nspr/pr/src/misc/prerror.c",
+      "nspr/pr/src/misc/prerrortable.c",
+      "nspr/pr/src/misc/prinit.c",
+      "nspr/pr/src/misc/prinrval.c",
+      "nspr/pr/src/misc/pripc.c",
+      "nspr/pr/src/misc/pripcsem.c",
+      "nspr/pr/src/misc/prlog2.c",
+      "nspr/pr/src/misc/prlong.c",
+      "nspr/pr/src/misc/prnetdb.c",
+      "nspr/pr/src/misc/prolock.c",
+      "nspr/pr/src/misc/prrng.c",
+      "nspr/pr/src/misc/prsystem.c",
+      "nspr/pr/src/misc/prthinfo.c",
+      "nspr/pr/src/misc/prtime.c",
+      "nspr/pr/src/misc/prtpool.c",
+      "nspr/pr/src/misc/prtrace.c",
+      "nspr/pr/src/pthreads/ptio.c",
+      "nspr/pr/src/pthreads/ptmisc.c",
+      "nspr/pr/src/pthreads/ptsynch.c",
+      "nspr/pr/src/pthreads/ptthread.c",
+      "nspr/pr/src/threads/combined/prucpu.c",
+      "nspr/pr/src/threads/combined/prucv.c",
+      "nspr/pr/src/threads/combined/prulock.c",
+      "nspr/pr/src/threads/combined/prustack.c",
+      "nspr/pr/src/threads/combined/pruthr.c",
+      "nspr/pr/src/threads/prcmon.c",
+      "nspr/pr/src/threads/prcthr.c",
+      "nspr/pr/src/threads/prdump.c",
+      "nspr/pr/src/threads/prmon.c",
+      "nspr/pr/src/threads/prrwlock.c",
+      "nspr/pr/src/threads/prsem.c",
+      "nspr/pr/src/threads/prtpd.c",
+    ]
+
+    public_configs = [ ":nspr_config" ]
+
+    configs -= [ "//build/config/compiler:chromium_code" ]
+    if (is_win) {
+      configs -= [
+        "//build/config/win:unicode",  # Requires 8-bit mode.
+        "//build/config/win:lean_and_mean",  # Won"t compile with lean and mean.
+      ]
+    }
+    configs += [
+      "//build/config/compiler:no_chromium_code",
+      "//build/config/compiler:no_size_t_to_int_warning",
+    ]
+
+    cflags = []
+    defines = [
+      "_NSPR_BUILD_",
+      "FORCE_PR_LOG",
+    ]
+
+    include_dirs = [ "nspr/pr/include/private" ]
+
+    if (is_win) {
+      cflags = [ "/wd4554" ]  # Check precidence.
+      defines += [
+        "XP_PC",
+        "WIN32",
+        "WIN95",
+        "_PR_GLOBAL_THREADS_ONLY",
+        "_CRT_SECURE_NO_WARNINGS",
+      ]
+    } else {
+      sources -= [
+        "nspr/pr/src/md/windows/ntgc.c",
+        "nspr/pr/src/md/windows/ntinrval.c",
+        "nspr/pr/src/md/windows/ntmisc.c",
+        "nspr/pr/src/md/windows/ntsec.c",
+        "nspr/pr/src/md/windows/ntsem.c",
+        "nspr/pr/src/md/windows/w32ipcsem.c",
+        "nspr/pr/src/md/windows/w32poll.c",
+        "nspr/pr/src/md/windows/w32rng.c",
+        "nspr/pr/src/md/windows/w32shm.c",
+        "nspr/pr/src/md/windows/w95cv.c",
+        "nspr/pr/src/md/windows/w95dllmain.c",
+        "nspr/pr/src/md/windows/w95io.c",
+        "nspr/pr/src/md/windows/w95sock.c",
+        "nspr/pr/src/md/windows/w95thred.c",
+        "nspr/pr/src/md/windows/win32_errors.c",
+        "nspr/pr/src/threads/combined/prucpu.c",
+        "nspr/pr/src/threads/combined/prucv.c",
+        "nspr/pr/src/threads/combined/prulock.c",
+        "nspr/pr/src/threads/combined/prustack.c",
+        "nspr/pr/src/threads/combined/pruthr.c",
+      ]
+    }
+
+    if (!is_posix) {
+      sources -= [
+        "nspr/pr/src/md/unix/darwin.c",
+        "nspr/pr/src/md/unix/os_Darwin.s",
+        "nspr/pr/src/md/unix/unix.c",
+        "nspr/pr/src/md/unix/unix_errors.c",
+        "nspr/pr/src/md/unix/uxproces.c",
+        "nspr/pr/src/md/unix/uxrng.c",
+        "nspr/pr/src/md/unix/uxshm.c",
+        "nspr/pr/src/md/unix/uxwrap.c",
+        "nspr/pr/src/pthreads/ptio.c",
+        "nspr/pr/src/pthreads/ptmisc.c",
+        "nspr/pr/src/pthreads/ptsynch.c",
+        "nspr/pr/src/pthreads/ptthread.c",
+      ]
+    }
+
+    if (current_cpu == "x86") {
+      defines += [ "_X86_" ]
+    } else if (current_cpu == "x64") {
+      defines += [ "_AMD64_" ]
+    }
+
+    if (is_mac || is_ios) {
+      sources -= [
+        "nspr/pr/src/io/prdir.c",
+        "nspr/pr/src/io/prfile.c",
+        "nspr/pr/src/io/prio.c",
+        "nspr/pr/src/io/prsocket.c",
+        "nspr/pr/src/misc/pripcsem.c",
+        "nspr/pr/src/threads/prcthr.c",
+        "nspr/pr/src/threads/prdump.c",
+        "nspr/pr/src/threads/prmon.c",
+        "nspr/pr/src/threads/prsem.c",
+      ]
+      defines += [
+        "XP_UNIX",
+        "DARWIN",
+        "XP_MACOSX",
+        "_PR_PTHREADS",
+        "HAVE_BSD_FLOCK",
+        "HAVE_DLADDR",
+        "HAVE_LCHOWN",
+        "HAVE_SOCKLEN_T",
+        "HAVE_STRERROR",
+      ]
+    }
+
+    if (is_mac) {
+      defines += [ "HAVE_CRT_EXTERNS_H" ]
+      libs = [
+        "CoreFoundation.framework",
+        "CoreServices.framework",
+      ]
+    }
+
+    if (is_clang) {
+      cflags += [
+        # nspr uses a bunch of deprecated functions (NSLinkModule etc) in
+        # prlink.c on mac.
+        "-Wno-deprecated-declarations",
+
+        # nspr passes "const char*" through "void*".
+        "-Wno-incompatible-pointer-types",
+
+        # nspr passes "int*" through "unsigned int*".
+        "-Wno-pointer-sign",
+      ]
+
+      # nspr uses assert(!"foo") instead of assert(false && "foo").
+      configs -= [ "//build/config/clang:extra_warnings" ]
+    }
+  }
+
+  component("nss") {
+    output_name = "crnss"
+    sources = [
+      # Ensure at least one object file is produced, so that MSVC does not
+      # warn when creating the static/shared library. See the note for
+      # the "nssckbi" target for why the "nss" target was split as such.
+      "nss/lib/nss/nssver.c",
+    ]
+
+    public_deps = [ ":nss_static" ]
+
+    if (include_nss_root_certs) {
+      public_deps += [ ":nssckbi" ]
+    }
+
+    if (component_mode == "shared_library") {
+      if (is_mac) {
+        ldflags = [ "-all_load" ]
+      } else if (is_win) {
+        # Pass the def file to the linker.
+        ldflags =
+            [ "/DEF:" + rebase_path("nss/exports_win.def", root_build_dir) ]
+      }
+    }
+  }
+
+  config("nssckbi_config") {
+    include_dirs = [ "nss/lib/ckfw/builtins" ]
+  }
+
+  # This is really more of a pseudo-target to work around the fact that
+  # a single static_library target cannot contain two object files of the
+  # same name (hash.o / hash.obj). Logically, this is part of the
+  # "nss_static" target. By separating it out, it creates a possible
+  # circular dependency between "nss_static" and "nssckbi" when
+  # "exclude_nss_root_certs" is not specified, as "nss_static" depends on
+  # the "builtinsC_GetFunctionList" exported by this target. This is an
+  # artifact of how NSS is being statically built, which is not an
+  # officially supported configuration - normally, "nssckbi.dll/so" would
+  # depend on libnss3.dll/so, and the higher layer caller would instruct
+  # libnss3.dll to dynamically load nssckbi.dll, breaking the circle.
+  #
+  # TODO(rsleevi): http://crbug.com/128134 - Break the circular dependency
+  # without requiring nssckbi to be built as a shared library.
+  source_set("nssckbi") {
+    visibility = [ ":nss" ]  # This target is internal implementation detail.
+
+    sources = [
+      "nss/lib/ckfw/builtins/anchor.c",
+      "nss/lib/ckfw/builtins/bfind.c",
+      "nss/lib/ckfw/builtins/binst.c",
+      "nss/lib/ckfw/builtins/bobject.c",
+      "nss/lib/ckfw/builtins/bsession.c",
+      "nss/lib/ckfw/builtins/bslot.c",
+      "nss/lib/ckfw/builtins/btoken.c",
+      "nss/lib/ckfw/builtins/builtins.h",
+      "nss/lib/ckfw/builtins/certdata.c",
+      "nss/lib/ckfw/builtins/ckbiver.c",
+      "nss/lib/ckfw/builtins/constants.c",
+      "nss/lib/ckfw/builtins/nssckbi.h",
+      "nss/lib/ckfw/ck.h",
+      "nss/lib/ckfw/ckfw.h",
+      "nss/lib/ckfw/ckfwm.h",
+      "nss/lib/ckfw/ckfwtm.h",
+      "nss/lib/ckfw/ckmd.h",
+      "nss/lib/ckfw/ckt.h",
+      "nss/lib/ckfw/crypto.c",
+      "nss/lib/ckfw/find.c",
+      "nss/lib/ckfw/hash.c",
+      "nss/lib/ckfw/instance.c",
+      "nss/lib/ckfw/mechanism.c",
+      "nss/lib/ckfw/mutex.c",
+      "nss/lib/ckfw/nssck.api",
+      "nss/lib/ckfw/nssckepv.h",
+      "nss/lib/ckfw/nssckft.h",
+      "nss/lib/ckfw/nssckfw.h",
+      "nss/lib/ckfw/nssckfwc.h",
+      "nss/lib/ckfw/nssckfwt.h",
+      "nss/lib/ckfw/nssckg.h",
+      "nss/lib/ckfw/nssckmdt.h",
+      "nss/lib/ckfw/nssckt.h",
+      "nss/lib/ckfw/object.c",
+      "nss/lib/ckfw/session.c",
+      "nss/lib/ckfw/sessobj.c",
+      "nss/lib/ckfw/slot.c",
+      "nss/lib/ckfw/token.c",
+      "nss/lib/ckfw/wrap.c",
+    ]
+
+    configs -= [ "//build/config/compiler:chromium_code" ]
+
+    if (is_win) {
+      configs -= [ "//build/config/win:unicode" ]  # Requires 8-bit mode.
+    }
+    configs += [ "//build/config/compiler:no_chromium_code" ]
+
+    include_dirs = [ "nss/lib/ckfw" ]
+    public_configs = [ ":nssckbi_config" ]
+
+    public_deps = [ ":nss_static" ]
+  }
+
+  config("nss_static_config") {
+    defines = [
+      "NSS_STATIC",
+      "NSS_USE_STATIC_LIBS",
+      "USE_UTIL_DIRECTLY",
+    ]
+    if (is_win) {
+      defines += [ "_WINDOWS" ]
+    }
+    include_dirs = [
+      "nspr/pr/include",
+      "nspr/lib/ds",
+      "nspr/lib/libc/include",
+      "nss/lib/base",
+      "nss/lib/certdb",
+      "nss/lib/certhigh",
+      "nss/lib/cryptohi",
+      "nss/lib/dev",
+      "nss/lib/freebl",
+      "nss/lib/freebl/ecl",
+      "nss/lib/nss",
+      "nss/lib/pk11wrap",
+      "nss/lib/pkcs7",
+      "nss/lib/pki",
+      "nss/lib/smime",
+      "nss/lib/softoken",
+      "nss/lib/util",
+    ]
+  }
+
+  if (is_win && current_cpu == "x86") {
+    source_set("nss_static_avx") {
+      sources = [
+        "nss/lib/freebl/intel-gcm-wrap.c",
+        "nss/lib/freebl/intel-gcm-x86-masm.asm",
+        "nss/lib/freebl/intel-gcm.h",
+      ]
+      defines = [
+        "_WINDOWS",
+        "_X86_",
+        "INTEL_GCM",
+        "MP_API_COMPATIBLE",
+        "MP_ASSEMBLY_DIV_2DX1D",
+        "MP_ASSEMBLY_MULTIPLY",
+        "MP_ASSEMBLY_SQUARE",
+        "MP_NO_MP_WORD",
+        "MP_USE_UINT_DIGIT",
+        "NSS_DISABLE_DBM",
+        "NSS_STATIC",
+        "NSS_USE_STATIC_LIBS",
+        "NSS_X86",
+        "NSS_X86_OR_X64",
+        "RIJNDAEL_INCLUDE_TABLES",
+        "SHLIB_PREFIX=\"\"",
+        "SHLIB_SUFFIX=\"dll\"",
+        "SHLIB_VERSION=\"3\"",
+        "SOFTOKEN_LIB_NAME=\"softokn3.dll\"",
+        "SOFTOKEN_SHLIB_VERSION=\"3\"",
+        "USE_HW_AES",
+        "USE_UTIL_DIRECTLY",
+        "WIN32",
+        "WIN95",
+        "XP_PC",
+      ]
+      include_dirs = [
+        "nspr/pr/include",
+        "nspr/lib/ds",
+        "nspr/lib/libc/include",
+        "nss/lib/freebl/ecl",
+        "nss/lib/util",
+      ]
+    }
+  }
+
+  source_set("nss_static") {
+    visibility = [ ":*" ]  # Internal implementation detail.
+
+    sources = [
+      "nss/lib/base/arena.c",
+      "nss/lib/base/base.h",
+      "nss/lib/base/baset.h",
+      "nss/lib/base/error.c",
+      "nss/lib/base/errorval.c",
+      "nss/lib/base/hash.c",
+      "nss/lib/base/hashops.c",
+      "nss/lib/base/item.c",
+      "nss/lib/base/libc.c",
+      "nss/lib/base/list.c",
+      "nss/lib/base/nssbase.h",
+      "nss/lib/base/nssbaset.h",
+      "nss/lib/base/nssutf8.c",
+      "nss/lib/base/tracker.c",
+      "nss/lib/certdb/alg1485.c",
+      "nss/lib/certdb/cert.h",
+      "nss/lib/certdb/certdb.c",
+      "nss/lib/certdb/certdb.h",
+      "nss/lib/certdb/certi.h",
+      "nss/lib/certdb/certt.h",
+      "nss/lib/certdb/certv3.c",
+      "nss/lib/certdb/certxutl.c",
+      "nss/lib/certdb/certxutl.h",
+      "nss/lib/certdb/crl.c",
+      "nss/lib/certdb/genname.c",
+      "nss/lib/certdb/genname.h",
+      "nss/lib/certdb/polcyxtn.c",
+      "nss/lib/certdb/secname.c",
+      "nss/lib/certdb/stanpcertdb.c",
+      "nss/lib/certdb/xauthkid.c",
+      "nss/lib/certdb/xbsconst.c",
+      "nss/lib/certdb/xconst.c",
+      "nss/lib/certdb/xconst.h",
+      "nss/lib/certhigh/certhigh.c",
+      "nss/lib/certhigh/certhtml.c",
+      "nss/lib/certhigh/certreq.c",
+      "nss/lib/certhigh/certvfy.c",
+      "nss/lib/certhigh/crlv2.c",
+      "nss/lib/certhigh/ocsp.c",
+      "nss/lib/certhigh/ocsp.h",
+      "nss/lib/certhigh/ocspi.h",
+      "nss/lib/certhigh/ocspsig.c",
+      "nss/lib/certhigh/ocspt.h",
+      "nss/lib/certhigh/ocspti.h",
+      "nss/lib/certhigh/xcrldist.c",
+      "nss/lib/cryptohi/cryptohi.h",
+      "nss/lib/cryptohi/cryptoht.h",
+      "nss/lib/cryptohi/dsautil.c",
+      "nss/lib/cryptohi/key.h",
+      "nss/lib/cryptohi/keyhi.h",
+      "nss/lib/cryptohi/keyi.h",
+      "nss/lib/cryptohi/keyt.h",
+      "nss/lib/cryptohi/keythi.h",
+      "nss/lib/cryptohi/sechash.c",
+      "nss/lib/cryptohi/sechash.h",
+      "nss/lib/cryptohi/seckey.c",
+      "nss/lib/cryptohi/secsign.c",
+      "nss/lib/cryptohi/secvfy.c",
+      "nss/lib/dev/ckhelper.c",
+      "nss/lib/dev/ckhelper.h",
+      "nss/lib/dev/dev.h",
+      "nss/lib/dev/devm.h",
+      "nss/lib/dev/devslot.c",
+      "nss/lib/dev/devt.h",
+      "nss/lib/dev/devtm.h",
+      "nss/lib/dev/devtoken.c",
+      "nss/lib/dev/devutil.c",
+      "nss/lib/dev/nssdev.h",
+      "nss/lib/dev/nssdevt.h",
+      "nss/lib/freebl/aeskeywrap.c",
+      "nss/lib/freebl/alg2268.c",
+      "nss/lib/freebl/alghmac.c",
+      "nss/lib/freebl/alghmac.h",
+      "nss/lib/freebl/arcfive.c",
+      "nss/lib/freebl/arcfour.c",
+      "nss/lib/freebl/blapi.h",
+      "nss/lib/freebl/blapii.h",
+      "nss/lib/freebl/blapit.h",
+      "nss/lib/freebl/camellia.c",
+      "nss/lib/freebl/camellia.h",
+      "nss/lib/freebl/chacha20/chacha20.c",
+      "nss/lib/freebl/chacha20/chacha20.h",
+      "nss/lib/freebl/chacha20/chacha20_vec.c",
+      "nss/lib/freebl/chacha20poly1305.c",
+      "nss/lib/freebl/chacha20poly1305.h",
+      "nss/lib/freebl/ctr.c",
+      "nss/lib/freebl/ctr.h",
+      "nss/lib/freebl/cts.c",
+      "nss/lib/freebl/cts.h",
+      "nss/lib/freebl/des.c",
+      "nss/lib/freebl/des.h",
+      "nss/lib/freebl/desblapi.c",
+      "nss/lib/freebl/dh.c",
+      "nss/lib/freebl/drbg.c",
+      "nss/lib/freebl/dsa.c",
+      "nss/lib/freebl/ec.c",
+      "nss/lib/freebl/ec.h",
+      "nss/lib/freebl/ecdecode.c",
+      "nss/lib/freebl/ecl/ec2.h",
+      "nss/lib/freebl/ecl/ec_naf.c",
+      "nss/lib/freebl/ecl/ecl-curve.h",
+      "nss/lib/freebl/ecl/ecl-exp.h",
+      "nss/lib/freebl/ecl/ecl-priv.h",
+      "nss/lib/freebl/ecl/ecl.c",
+      "nss/lib/freebl/ecl/ecl.h",
+      "nss/lib/freebl/ecl/ecl_curve.c",
+      "nss/lib/freebl/ecl/ecl_gf.c",
+      "nss/lib/freebl/ecl/ecl_mult.c",
+      "nss/lib/freebl/ecl/ecp.h",
+      "nss/lib/freebl/ecl/ecp_256.c",
+      "nss/lib/freebl/ecl/ecp_256_32.c",
+      "nss/lib/freebl/ecl/ecp_384.c",
+      "nss/lib/freebl/ecl/ecp_521.c",
+      "nss/lib/freebl/ecl/ecp_aff.c",
+      "nss/lib/freebl/ecl/ecp_jac.c",
+      "nss/lib/freebl/ecl/ecp_jm.c",
+      "nss/lib/freebl/ecl/ecp_mont.c",
+      "nss/lib/freebl/gcm.c",
+      "nss/lib/freebl/gcm.h",
+      "nss/lib/freebl/hmacct.c",
+      "nss/lib/freebl/hmacct.h",
+      "nss/lib/freebl/intel-aes-x86-masm.asm",
+      "nss/lib/freebl/intel-aes.h",
+      "nss/lib/freebl/jpake.c",
+      "nss/lib/freebl/md2.c",
+      "nss/lib/freebl/md5.c",
+      "nss/lib/freebl/mpi/logtab.h",
+      "nss/lib/freebl/mpi/mp_gf2m-priv.h",
+      "nss/lib/freebl/mpi/mp_gf2m.c",
+      "nss/lib/freebl/mpi/mp_gf2m.h",
+      "nss/lib/freebl/mpi/mpcpucache.c",
+      "nss/lib/freebl/mpi/mpi-config.h",
+      "nss/lib/freebl/mpi/mpi-priv.h",
+      "nss/lib/freebl/mpi/mpi.c",
+      "nss/lib/freebl/mpi/mpi.h",
+      "nss/lib/freebl/mpi/mpi_amd64.c",
+      "nss/lib/freebl/mpi/mpi_arm.c",
+      "nss/lib/freebl/mpi/mpi_arm_mac.c",
+      "nss/lib/freebl/mpi/mpi_x86_asm.c",
+      "nss/lib/freebl/mpi/mplogic.c",
+      "nss/lib/freebl/mpi/mplogic.h",
+      "nss/lib/freebl/mpi/mpmontg.c",
+      "nss/lib/freebl/mpi/mpprime.c",
+      "nss/lib/freebl/mpi/mpprime.h",
+      "nss/lib/freebl/mpi/primes.c",
+      "nss/lib/freebl/nss_build_config_mac.h",
+      "nss/lib/freebl/poly1305/poly1305-donna-x64-sse2-incremental-source.c",
+      "nss/lib/freebl/poly1305/poly1305.c",
+      "nss/lib/freebl/poly1305/poly1305.h",
+      "nss/lib/freebl/pqg.c",
+      "nss/lib/freebl/pqg.h",
+      "nss/lib/freebl/rawhash.c",
+      "nss/lib/freebl/rijndael.c",
+      "nss/lib/freebl/rijndael.h",
+      "nss/lib/freebl/rijndael32.tab",
+      "nss/lib/freebl/rsa.c",
+      "nss/lib/freebl/rsapkcs.c",
+      "nss/lib/freebl/secmpi.h",
+      "nss/lib/freebl/secrng.h",
+      "nss/lib/freebl/seed.c",
+      "nss/lib/freebl/seed.h",
+      "nss/lib/freebl/sha256.h",
+      "nss/lib/freebl/sha512.c",
+      "nss/lib/freebl/sha_fast.c",
+      "nss/lib/freebl/sha_fast.h",
+      "nss/lib/freebl/shsign.h",
+      "nss/lib/freebl/shvfy.c",
+      "nss/lib/freebl/sysrand.c",
+      "nss/lib/freebl/tlsprfalg.c",
+      "nss/lib/freebl/unix_rand.c",
+      "nss/lib/freebl/win_rand.c",
+      "nss/lib/nss/nss.h",
+      "nss/lib/nss/nssinit.c",
+      "nss/lib/nss/nssrenam.h",
+      "nss/lib/nss/utilwrap.c",
+      "nss/lib/pk11wrap/debug_module.c",
+      "nss/lib/pk11wrap/dev3hack.c",
+      "nss/lib/pk11wrap/dev3hack.h",
+      "nss/lib/pk11wrap/pk11akey.c",
+      "nss/lib/pk11wrap/pk11auth.c",
+      "nss/lib/pk11wrap/pk11cert.c",
+      "nss/lib/pk11wrap/pk11cxt.c",
+      "nss/lib/pk11wrap/pk11err.c",
+      "nss/lib/pk11wrap/pk11func.h",
+      "nss/lib/pk11wrap/pk11kea.c",
+      "nss/lib/pk11wrap/pk11list.c",
+      "nss/lib/pk11wrap/pk11load.c",
+      "nss/lib/pk11wrap/pk11mech.c",
+      "nss/lib/pk11wrap/pk11merge.c",
+      "nss/lib/pk11wrap/pk11nobj.c",
+      "nss/lib/pk11wrap/pk11obj.c",
+      "nss/lib/pk11wrap/pk11pars.c",
+      "nss/lib/pk11wrap/pk11pbe.c",
+      "nss/lib/pk11wrap/pk11pk12.c",
+      "nss/lib/pk11wrap/pk11pqg.c",
+      "nss/lib/pk11wrap/pk11pqg.h",
+      "nss/lib/pk11wrap/pk11priv.h",
+      "nss/lib/pk11wrap/pk11pub.h",
+      "nss/lib/pk11wrap/pk11sdr.c",
+      "nss/lib/pk11wrap/pk11sdr.h",
+      "nss/lib/pk11wrap/pk11skey.c",
+      "nss/lib/pk11wrap/pk11slot.c",
+      "nss/lib/pk11wrap/pk11util.c",
+      "nss/lib/pk11wrap/secmod.h",
+      "nss/lib/pk11wrap/secmodi.h",
+      "nss/lib/pk11wrap/secmodt.h",
+      "nss/lib/pk11wrap/secmodti.h",
+      "nss/lib/pk11wrap/secpkcs5.h",
+      "nss/lib/pkcs7/certread.c",
+      "nss/lib/pkcs7/p7common.c",
+      "nss/lib/pkcs7/p7create.c",
+      "nss/lib/pkcs7/p7decode.c",
+      "nss/lib/pkcs7/p7encode.c",
+      "nss/lib/pkcs7/p7local.c",
+      "nss/lib/pkcs7/p7local.h",
+      "nss/lib/pkcs7/pkcs7t.h",
+      "nss/lib/pkcs7/secmime.c",
+      "nss/lib/pkcs7/secmime.h",
+      "nss/lib/pkcs7/secpkcs7.h",
+      "nss/lib/pki/asymmkey.c",
+      "nss/lib/pki/certdecode.c",
+      "nss/lib/pki/certificate.c",
+      "nss/lib/pki/cryptocontext.c",
+      "nss/lib/pki/nsspki.h",
+      "nss/lib/pki/nsspkit.h",
+      "nss/lib/pki/pki.h",
+      "nss/lib/pki/pki3hack.c",
+      "nss/lib/pki/pki3hack.h",
+      "nss/lib/pki/pkibase.c",
+      "nss/lib/pki/pkim.h",
+      "nss/lib/pki/pkistore.c",
+      "nss/lib/pki/pkistore.h",
+      "nss/lib/pki/pkit.h",
+      "nss/lib/pki/pkitm.h",
+      "nss/lib/pki/symmkey.c",
+      "nss/lib/pki/tdcache.c",
+      "nss/lib/pki/trustdomain.c",
+      "nss/lib/smime/cms.h",
+      "nss/lib/smime/cmslocal.h",
+      "nss/lib/smime/cmsreclist.h",
+      "nss/lib/smime/cmst.h",
+      "nss/lib/smime/smime.h",
+      "nss/lib/softoken/fipsaudt.c",
+      "nss/lib/softoken/fipstest.c",
+      "nss/lib/softoken/fipstokn.c",
+      "nss/lib/softoken/jpakesftk.c",
+      "nss/lib/softoken/lgglue.c",
+      "nss/lib/softoken/lgglue.h",
+      "nss/lib/softoken/lowkey.c",
+      "nss/lib/softoken/lowkeyi.h",
+      "nss/lib/softoken/lowkeyti.h",
+      "nss/lib/softoken/lowpbe.c",
+      "nss/lib/softoken/lowpbe.h",
+      "nss/lib/softoken/padbuf.c",
+      "nss/lib/softoken/pkcs11.c",
+      "nss/lib/softoken/pkcs11c.c",
+      "nss/lib/softoken/pkcs11i.h",
+      "nss/lib/softoken/pkcs11ni.h",
+      "nss/lib/softoken/pkcs11u.c",
+      "nss/lib/softoken/sdb.c",
+      "nss/lib/softoken/sdb.h",
+      "nss/lib/softoken/sftkdb.c",
+      "nss/lib/softoken/sftkdb.h",
+      "nss/lib/softoken/sftkdbt.h",
+      "nss/lib/softoken/sftkdbti.h",
+      "nss/lib/softoken/sftkhmac.c",
+      "nss/lib/softoken/sftkpars.c",
+      "nss/lib/softoken/sftkpars.h",
+      "nss/lib/softoken/sftkpwd.c",
+      "nss/lib/softoken/softkver.c",
+      "nss/lib/softoken/softkver.h",
+      "nss/lib/softoken/softoken.h",
+      "nss/lib/softoken/softoknt.h",
+      "nss/lib/softoken/tlsprf.c",
+      "nss/lib/ssl/sslerr.h",
+      "nss/lib/util/SECerrs.h",
+      "nss/lib/util/base64.h",
+      "nss/lib/util/ciferfam.h",
+      "nss/lib/util/derdec.c",
+      "nss/lib/util/derenc.c",
+      "nss/lib/util/dersubr.c",
+      "nss/lib/util/dertime.c",
+      "nss/lib/util/errstrs.c",
+      "nss/lib/util/hasht.h",
+      "nss/lib/util/nssb64.h",
+      "nss/lib/util/nssb64d.c",
+      "nss/lib/util/nssb64e.c",
+      "nss/lib/util/nssb64t.h",
+      "nss/lib/util/nssilckt.h",
+      "nss/lib/util/nssilock.c",
+      "nss/lib/util/nssilock.h",
+      "nss/lib/util/nsslocks.h",
+      "nss/lib/util/nssrwlk.c",
+      "nss/lib/util/nssrwlk.h",
+      "nss/lib/util/nssrwlkt.h",
+      "nss/lib/util/nssutil.h",
+      "nss/lib/util/oidstring.c",
+      "nss/lib/util/pkcs11.h",
+      "nss/lib/util/pkcs11f.h",
+      "nss/lib/util/pkcs11n.h",
+      "nss/lib/util/pkcs11p.h",
+      "nss/lib/util/pkcs11t.h",
+      "nss/lib/util/pkcs11u.h",
+      "nss/lib/util/pkcs1sig.c",
+      "nss/lib/util/pkcs1sig.h",
+      "nss/lib/util/portreg.c",
+      "nss/lib/util/portreg.h",
+      "nss/lib/util/quickder.c",
+      "nss/lib/util/secalgid.c",
+      "nss/lib/util/secasn1.h",
+      "nss/lib/util/secasn1d.c",
+      "nss/lib/util/secasn1e.c",
+      "nss/lib/util/secasn1t.h",
+      "nss/lib/util/secasn1u.c",
+      "nss/lib/util/seccomon.h",
+      "nss/lib/util/secder.h",
+      "nss/lib/util/secdert.h",
+      "nss/lib/util/secdig.c",
+      "nss/lib/util/secdig.h",
+      "nss/lib/util/secdigt.h",
+      "nss/lib/util/secerr.h",
+      "nss/lib/util/secitem.c",
+      "nss/lib/util/secitem.h",
+      "nss/lib/util/secoid.c",
+      "nss/lib/util/secoid.h",
+      "nss/lib/util/secoidt.h",
+      "nss/lib/util/secport.c",
+      "nss/lib/util/secport.h",
+      "nss/lib/util/sectime.c",
+      "nss/lib/util/templates.c",
+      "nss/lib/util/utf8.c",
+      "nss/lib/util/utilmod.c",
+      "nss/lib/util/utilmodt.h",
+      "nss/lib/util/utilpars.c",
+      "nss/lib/util/utilpars.h",
+      "nss/lib/util/utilparst.h",
+      "nss/lib/util/utilrename.h",
+    ]
+
+    sources -= [
+      # mpi_arm.c is included by mpi_arm_mac.c.
+      # NOTE: mpi_arm.c can be used directly on Linux. mpi_arm.c will need
+      # to be excluded conditionally if we start to build NSS on Linux.
+      "nss/lib/freebl/mpi/mpi_arm.c",
+
+      # primes.c is included by mpprime.c.
+      "nss/lib/freebl/mpi/primes.c",
+
+      # unix_rand.c and win_rand.c are included by sysrand.c.
+      "nss/lib/freebl/unix_rand.c",
+      "nss/lib/freebl/win_rand.c",
+
+      # debug_module.c is included by pk11load.c.
+      "nss/lib/pk11wrap/debug_module.c",
+    ]
+
+    configs -= [ "//build/config/compiler:chromium_code" ]
+    if (is_win) {
+      configs -= [ "//build/config/win:unicode" ]  # Requires 8-bit mode.
+    }
+    configs += [
+      "//build/config/compiler:no_chromium_code",
+      "//build/config/compiler:no_size_t_to_int_warning",
+    ]
+    public_configs = [ ":nss_static_config" ]
+
+    cflags = []
+
+    # Only need the defines and includes not in nss_static_config.
+    defines = [
+      "MP_API_COMPATIBLE",
+      "NSS_DISABLE_DBM",
+      "RIJNDAEL_INCLUDE_TABLES",
+      "SHLIB_VERSION=\"3\"",
+      "SOFTOKEN_SHLIB_VERSION=\"3\"",
+    ]
+    include_dirs = [
+      "nss/lib/freebl/mpi",
+      "nss/lib/ssl",
+    ]
+
+    if (is_win) {
+      cflags += [ "/wd4101" ]  # Unreferenced local variable.
+    }
+
+    if (include_nss_libpkix) {
+      sources += [
+        "nss/lib/certhigh/certvfypkix.c",
+        "nss/lib/certhigh/certvfypkixprint.c",
+        "nss/lib/libpkix/include/pkix.h",
+        "nss/lib/libpkix/include/pkix_certsel.h",
+        "nss/lib/libpkix/include/pkix_certstore.h",
+        "nss/lib/libpkix/include/pkix_checker.h",
+        "nss/lib/libpkix/include/pkix_crlsel.h",
+        "nss/lib/libpkix/include/pkix_errorstrings.h",
+        "nss/lib/libpkix/include/pkix_params.h",
+        "nss/lib/libpkix/include/pkix_pl_pki.h",
+        "nss/lib/libpkix/include/pkix_pl_system.h",
+        "nss/lib/libpkix/include/pkix_results.h",
+        "nss/lib/libpkix/include/pkix_revchecker.h",
+        "nss/lib/libpkix/include/pkix_sample_modules.h",
+        "nss/lib/libpkix/include/pkix_util.h",
+        "nss/lib/libpkix/include/pkixt.h",
+        "nss/lib/libpkix/pkix/certsel/pkix_certselector.c",
+        "nss/lib/libpkix/pkix/certsel/pkix_certselector.h",
+        "nss/lib/libpkix/pkix/certsel/pkix_comcertselparams.c",
+        "nss/lib/libpkix/pkix/certsel/pkix_comcertselparams.h",
+        "nss/lib/libpkix/pkix/checker/pkix_basicconstraintschecker.c",
+        "nss/lib/libpkix/pkix/checker/pkix_basicconstraintschecker.h",
+        "nss/lib/libpkix/pkix/checker/pkix_certchainchecker.c",
+        "nss/lib/libpkix/pkix/checker/pkix_certchainchecker.h",
+        "nss/lib/libpkix/pkix/checker/pkix_crlchecker.c",
+        "nss/lib/libpkix/pkix/checker/pkix_crlchecker.h",
+        "nss/lib/libpkix/pkix/checker/pkix_ekuchecker.c",
+        "nss/lib/libpkix/pkix/checker/pkix_ekuchecker.h",
+        "nss/lib/libpkix/pkix/checker/pkix_expirationchecker.c",
+        "nss/lib/libpkix/pkix/checker/pkix_expirationchecker.h",
+        "nss/lib/libpkix/pkix/checker/pkix_namechainingchecker.c",
+        "nss/lib/libpkix/pkix/checker/pkix_namechainingchecker.h",
+        "nss/lib/libpkix/pkix/checker/pkix_nameconstraintschecker.c",
+        "nss/lib/libpkix/pkix/checker/pkix_nameconstraintschecker.h",
+        "nss/lib/libpkix/pkix/checker/pkix_ocspchecker.c",
+        "nss/lib/libpkix/pkix/checker/pkix_ocspchecker.h",
+        "nss/lib/libpkix/pkix/checker/pkix_policychecker.c",
+        "nss/lib/libpkix/pkix/checker/pkix_policychecker.h",
+        "nss/lib/libpkix/pkix/checker/pkix_revocationchecker.c",
+        "nss/lib/libpkix/pkix/checker/pkix_revocationchecker.h",
+        "nss/lib/libpkix/pkix/checker/pkix_revocationmethod.c",
+        "nss/lib/libpkix/pkix/checker/pkix_revocationmethod.h",
+        "nss/lib/libpkix/pkix/checker/pkix_signaturechecker.c",
+        "nss/lib/libpkix/pkix/checker/pkix_signaturechecker.h",
+        "nss/lib/libpkix/pkix/checker/pkix_targetcertchecker.c",
+        "nss/lib/libpkix/pkix/checker/pkix_targetcertchecker.h",
+        "nss/lib/libpkix/pkix/crlsel/pkix_comcrlselparams.c",
+        "nss/lib/libpkix/pkix/crlsel/pkix_comcrlselparams.h",
+        "nss/lib/libpkix/pkix/crlsel/pkix_crlselector.c",
+        "nss/lib/libpkix/pkix/crlsel/pkix_crlselector.h",
+        "nss/lib/libpkix/pkix/params/pkix_procparams.c",
+        "nss/lib/libpkix/pkix/params/pkix_procparams.h",
+        "nss/lib/libpkix/pkix/params/pkix_resourcelimits.c",
+        "nss/lib/libpkix/pkix/params/pkix_resourcelimits.h",
+        "nss/lib/libpkix/pkix/params/pkix_trustanchor.c",
+        "nss/lib/libpkix/pkix/params/pkix_trustanchor.h",
+        "nss/lib/libpkix/pkix/params/pkix_valparams.c",
+        "nss/lib/libpkix/pkix/params/pkix_valparams.h",
+        "nss/lib/libpkix/pkix/results/pkix_buildresult.c",
+        "nss/lib/libpkix/pkix/results/pkix_buildresult.h",
+        "nss/lib/libpkix/pkix/results/pkix_policynode.c",
+        "nss/lib/libpkix/pkix/results/pkix_policynode.h",
+        "nss/lib/libpkix/pkix/results/pkix_valresult.c",
+        "nss/lib/libpkix/pkix/results/pkix_valresult.h",
+        "nss/lib/libpkix/pkix/results/pkix_verifynode.c",
+        "nss/lib/libpkix/pkix/results/pkix_verifynode.h",
+        "nss/lib/libpkix/pkix/store/pkix_store.c",
+        "nss/lib/libpkix/pkix/store/pkix_store.h",
+        "nss/lib/libpkix/pkix/top/pkix_build.c",
+        "nss/lib/libpkix/pkix/top/pkix_build.h",
+        "nss/lib/libpkix/pkix/top/pkix_lifecycle.c",
+        "nss/lib/libpkix/pkix/top/pkix_lifecycle.h",
+        "nss/lib/libpkix/pkix/top/pkix_validate.c",
+        "nss/lib/libpkix/pkix/top/pkix_validate.h",
+        "nss/lib/libpkix/pkix/util/pkix_error.c",
+        "nss/lib/libpkix/pkix/util/pkix_error.h",
+        "nss/lib/libpkix/pkix/util/pkix_errpaths.c",
+        "nss/lib/libpkix/pkix/util/pkix_list.c",
+        "nss/lib/libpkix/pkix/util/pkix_list.h",
+        "nss/lib/libpkix/pkix/util/pkix_logger.c",
+        "nss/lib/libpkix/pkix/util/pkix_logger.h",
+        "nss/lib/libpkix/pkix/util/pkix_tools.c",
+        "nss/lib/libpkix/pkix/util/pkix_tools.h",
+        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_aiamgr.c",
+        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_aiamgr.h",
+        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_colcertstore.c",
+        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_colcertstore.h",
+        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_httpcertstore.c",
+        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_httpcertstore.h",
+        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_httpdefaultclient.c",
+        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_httpdefaultclient.h",
+        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_nsscontext.c",
+        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_nsscontext.h",
+        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_pk11certstore.c",
+        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_pk11certstore.h",
+        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_socket.c",
+        "nss/lib/libpkix/pkix_pl_nss/module/pkix_pl_socket.h",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_basicconstraints.c",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_basicconstraints.h",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_cert.c",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_cert.h",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_certpolicyinfo.c",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_certpolicyinfo.h",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_certpolicymap.c",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_certpolicymap.h",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_certpolicyqualifier.c",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_certpolicyqualifier.h",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_crl.c",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_crl.h",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_crldp.c",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_crldp.h",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_crlentry.c",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_crlentry.h",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_date.c",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_date.h",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_generalname.c",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_generalname.h",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_infoaccess.c",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_infoaccess.h",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_nameconstraints.c",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_nameconstraints.h",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_ocspcertid.c",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_ocspcertid.h",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_ocsprequest.c",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_ocsprequest.h",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_ocspresponse.c",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_ocspresponse.h",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_publickey.c",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_publickey.h",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_x500name.c",
+        "nss/lib/libpkix/pkix_pl_nss/pki/pkix_pl_x500name.h",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_bigint.c",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_bigint.h",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_bytearray.c",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_bytearray.h",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_common.c",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_common.h",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_error.c",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_hashtable.c",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_hashtable.h",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_lifecycle.c",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_lifecycle.h",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_mem.c",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_mem.h",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_monitorlock.c",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_monitorlock.h",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_mutex.c",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_mutex.h",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_object.c",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_object.h",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_oid.c",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_oid.h",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_primhash.c",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_primhash.h",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_rwlock.c",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_rwlock.h",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_string.c",
+        "nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_string.h",
+      ]
+
+      # Disable the LDAP code in libpkix.
+      defines += [ "NSS_PKIX_NO_LDAP" ]
+
+      include_dirs += [
+        "nss/lib/libpkix/include",
+        "nss/lib/libpkix/pkix/certsel",
+        "nss/lib/libpkix/pkix/checker",
+        "nss/lib/libpkix/pkix/crlsel",
+        "nss/lib/libpkix/pkix/params",
+        "nss/lib/libpkix/pkix/results",
+        "nss/lib/libpkix/pkix/store",
+        "nss/lib/libpkix/pkix/top",
+        "nss/lib/libpkix/pkix/util",
+        "nss/lib/libpkix/pkix_pl_nss/module",
+        "nss/lib/libpkix/pkix_pl_nss/pki",
+        "nss/lib/libpkix/pkix_pl_nss/system",
+      ]
+    } else {
+      defines += [ "NSS_DISABLE_LIBPKIX" ]
+    }
+
+    if (!include_nss_root_certs) {
+      defines += [ "NSS_DISABLE_ROOT_CERTS" ]
+    }
+
+    if (current_cpu == "x64" && !is_win) {
+      sources -= [
+        "nss/lib/freebl/chacha20/chacha20.c",
+        "nss/lib/freebl/poly1305/poly1305.c",
+      ]
+    } else {
+      sources -= [
+        "nss/lib/freebl/chacha20/chacha20_vec.c",
+        "nss/lib/freebl/poly1305/poly1305-donna-x64-sse2-incremental-source.c",
+      ]
+    }
+
+    if (is_mac || is_ios) {
+      sources -= [ "nss/lib/freebl/mpi/mpi_amd64.c" ]
+      cflags += [
+        "-include",
+        rebase_path("//third_party/nss/nss/lib/freebl/nss_build_config_mac.h",
+                    root_build_dir),
+      ]
+      defines += [
+        "XP_UNIX",
+        "DARWIN",
+        "HAVE_STRERROR",
+        "HAVE_BSD_FLOCK",
+        "SHLIB_SUFFIX=\"dylib\"",
+        "SHLIB_PREFIX=\"lib\"",
+        "SOFTOKEN_LIB_NAME=\"libsoftokn3.dylib\"",
+      ]
+
+      configs -= [ "//build/config/gcc:symbol_visibility_hidden" ]
+    } else {
+      # Not Mac/iOS.
+      sources -= [ "nss/lib/freebl/mpi/mpi_arm_mac.c" ]
+    }
+
+    if (is_win) {
+      defines += [
+        "SHLIB_SUFFIX=\"dll\"",
+        "SHLIB_PREFIX=\"\"",
+        "SOFTOKEN_LIB_NAME=\"softokn3.dll\"",
+        "XP_PC",
+        "WIN32",
+        "WIN95",
+      ]
+
+      if (current_cpu == "x86") {
+        defines += [
+          "NSS_X86_OR_X64",
+          "NSS_X86",
+          "_X86_",
+          "MP_ASSEMBLY_MULTIPLY",
+          "MP_ASSEMBLY_SQUARE",
+          "MP_ASSEMBLY_DIV_2DX1D",
+          "MP_USE_UINT_DIGIT",
+          "MP_NO_MP_WORD",
+          "USE_HW_AES",
+          "INTEL_GCM",
+        ]
+        sources -= [ "nss/lib/freebl/mpi/mpi_amd64.c" ]
+      } else if (current_cpu == "x64") {
+        sources -= [
+          "nss/lib/freebl/intel-aes-x86-masm.asm",
+          "nss/lib/freebl/mpi/mpi_amd64.c",
+          "nss/lib/freebl/mpi/mpi_x86_asm.c",
+        ]
+        defines += [
+          "NSS_USE_64",
+          "NSS_X86_OR_X64",
+          "NSS_X64",
+          "_AMD64_",
+          "MP_CHAR_STORE_SLOW",
+          "MP_IS_LITTLE_ENDIAN",
+          "WIN64",
+        ]
+      }
+    } else {
+      # Not Windows.
+      sources -= [
+        # mpi_x86_asm.c contains MSVC inline assembly code.
+        "nss/lib/freebl/mpi/mpi_x86_asm.c",
+      ]
+    }
+
+    if (is_clang) {
+      cflags += [
+        # nss doesn"t explicitly cast between different enum types.
+        "-Wno-conversion",
+
+        # nss passes "const char*" through "void*".
+        "-Wno-incompatible-pointer-types",
+
+        # nss prefers `a && b || c` over `(a && b) || c`.
+        "-Wno-logical-op-parentheses",
+
+        # nss doesn"t use exhaustive switches on enums
+        "-Wno-switch",
+
+        # nss has some `unsigned < 0` checks.
+        "-Wno-tautological-compare",
+      ]
+    }
+
+    public_deps = [ ":nspr" ]
+    deps = [
+      ":nspr",
+      "//third_party/sqlite",
+    ]
+
+    if (is_win && current_cpu == "x86") {
+      deps += [ ":nss_static_avx" ]
+    }
+  }
+}  # Windows/Mac/iOS.
diff --git a/engine/src/flutter/build/secondary/third_party/ocmock/BUILD.gn b/engine/src/flutter/build/secondary/third_party/ocmock/BUILD.gn
new file mode 100644
index 00000000000..66f2e49f30f
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/ocmock/BUILD.gn
@@ -0,0 +1,121 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+ocmock_path = "//third_party/ocmock/Source"
+
+# OCMock headers use `#import <OCMock/Foo.h>`.
+config("ocmock_config") {
+  include_dirs = [ "$ocmock_path" ]
+}
+
+# Target that compiles all sources to .o files but does not produce a static
+# library for use in macOS desktop tests.
+source_set("ocmock_src") {
+  configs -= [
+    "//build/config/compiler:chromium_code",
+    "//build/config/gcc:symbol_visibility_hidden",
+    "//build/config:symbol_visibility_hidden",
+  ]
+  all_dependent_configs = [ ":ocmock_config" ]
+  cflags = [
+    "-fvisibility=default",
+    "-Wno-misleading-indentation",
+  ]
+  if (is_ios) {
+    cflags += [ "-mios-simulator-version-min=$ios_testing_deployment_target" ]
+  }
+
+  sources = [
+    "$ocmock_path/OCMock/NSInvocation+OCMAdditions.h",
+    "$ocmock_path/OCMock/NSInvocation+OCMAdditions.m",
+    "$ocmock_path/OCMock/NSMethodSignature+OCMAdditions.h",
+    "$ocmock_path/OCMock/NSMethodSignature+OCMAdditions.m",
+    "$ocmock_path/OCMock/NSNotificationCenter+OCMAdditions.h",
+    "$ocmock_path/OCMock/NSNotificationCenter+OCMAdditions.m",
+    "$ocmock_path/OCMock/NSObject+OCMAdditions.h",
+    "$ocmock_path/OCMock/NSObject+OCMAdditions.m",
+    "$ocmock_path/OCMock/NSValue+OCMAdditions.h",
+    "$ocmock_path/OCMock/NSValue+OCMAdditions.m",
+    "$ocmock_path/OCMock/OCClassMockObject.h",
+    "$ocmock_path/OCMock/OCClassMockObject.m",
+    "$ocmock_path/OCMock/OCMArg.h",
+    "$ocmock_path/OCMock/OCMArg.m",
+    "$ocmock_path/OCMock/OCMArgAction.h",
+    "$ocmock_path/OCMock/OCMArgAction.m",
+    "$ocmock_path/OCMock/OCMBlockArgCaller.h",
+    "$ocmock_path/OCMock/OCMBlockArgCaller.m",
+    "$ocmock_path/OCMock/OCMBlockCaller.h",
+    "$ocmock_path/OCMock/OCMBlockCaller.m",
+    "$ocmock_path/OCMock/OCMBoxedReturnValueProvider.h",
+    "$ocmock_path/OCMock/OCMBoxedReturnValueProvider.m",
+    "$ocmock_path/OCMock/OCMConstraint.h",
+    "$ocmock_path/OCMock/OCMConstraint.m",
+    "$ocmock_path/OCMock/OCMExceptionReturnValueProvider.h",
+    "$ocmock_path/OCMock/OCMExceptionReturnValueProvider.m",
+    "$ocmock_path/OCMock/OCMExpectationRecorder.h",
+    "$ocmock_path/OCMock/OCMExpectationRecorder.m",
+    "$ocmock_path/OCMock/OCMFunctions.h",
+    "$ocmock_path/OCMock/OCMFunctions.m",
+    "$ocmock_path/OCMock/OCMFunctionsPrivate.h",
+    "$ocmock_path/OCMock/OCMIndirectReturnValueProvider.h",
+    "$ocmock_path/OCMock/OCMIndirectReturnValueProvider.m",
+    "$ocmock_path/OCMock/OCMInvocationExpectation.h",
+    "$ocmock_path/OCMock/OCMInvocationExpectation.m",
+    "$ocmock_path/OCMock/OCMInvocationMatcher.h",
+    "$ocmock_path/OCMock/OCMInvocationMatcher.m",
+    "$ocmock_path/OCMock/OCMInvocationStub.h",
+    "$ocmock_path/OCMock/OCMInvocationStub.m",
+    "$ocmock_path/OCMock/OCMLocation.h",
+    "$ocmock_path/OCMock/OCMLocation.m",
+    "$ocmock_path/OCMock/OCMMacroState.h",
+    "$ocmock_path/OCMock/OCMMacroState.m",
+    "$ocmock_path/OCMock/OCMNonRetainingObjectReturnValueProvider.h",
+    "$ocmock_path/OCMock/OCMNonRetainingObjectReturnValueProvider.m",
+    "$ocmock_path/OCMock/OCMNotificationPoster.h",
+    "$ocmock_path/OCMock/OCMNotificationPoster.m",
+    "$ocmock_path/OCMock/OCMObjectReturnValueProvider.h",
+    "$ocmock_path/OCMock/OCMObjectReturnValueProvider.m",
+    "$ocmock_path/OCMock/OCMObserverRecorder.h",
+    "$ocmock_path/OCMock/OCMObserverRecorder.m",
+    "$ocmock_path/OCMock/OCMPassByRefSetter.h",
+    "$ocmock_path/OCMock/OCMPassByRefSetter.m",
+    "$ocmock_path/OCMock/OCMQuantifier.h",
+    "$ocmock_path/OCMock/OCMQuantifier.m",
+    "$ocmock_path/OCMock/OCMRealObjectForwarder.h",
+    "$ocmock_path/OCMock/OCMRealObjectForwarder.m",
+    "$ocmock_path/OCMock/OCMRecorder.h",
+    "$ocmock_path/OCMock/OCMRecorder.m",
+    "$ocmock_path/OCMock/OCMStubRecorder.h",
+    "$ocmock_path/OCMock/OCMStubRecorder.m",
+    "$ocmock_path/OCMock/OCMVerifier.h",
+    "$ocmock_path/OCMock/OCMVerifier.m",
+    "$ocmock_path/OCMock/OCMock.h",
+    "$ocmock_path/OCMock/OCMockObject.h",
+    "$ocmock_path/OCMock/OCMockObject.m",
+    "$ocmock_path/OCMock/OCObserverMockObject.h",
+    "$ocmock_path/OCMock/OCObserverMockObject.m",
+    "$ocmock_path/OCMock/OCPartialMockObject.h",
+    "$ocmock_path/OCMock/OCPartialMockObject.m",
+    "$ocmock_path/OCMock/OCProtocolMockObject.h",
+    "$ocmock_path/OCMock/OCProtocolMockObject.m",
+  ]
+
+  frameworks = [ "Foundation.framework" ]
+}
+
+shared_library("ocmock_shared") {
+  deps = [ ":ocmock_src" ]
+  cflags = [ "-fvisibility=default" ]
+  ldflags = [ "-Wl,-install_name,@rpath/Frameworks/libocmock_shared.dylib" ]
+}
+
+# Generates a static library, used in iOS unit test targets
+static_library("ocmock") {
+  # Force the static lib to include code from dependencies
+  complete_static_lib = true
+  if (is_ios) {
+    cflags = [ "-mios-simulator-version-min=$ios_testing_deployment_target" ]
+  }
+  public_deps = [ ":ocmock_src" ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/pkg/quiver/BUILD.gn b/engine/src/flutter/build/secondary/third_party/pkg/quiver/BUILD.gn
new file mode 100644
index 00000000000..8917550b308
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/pkg/quiver/BUILD.gn
@@ -0,0 +1,83 @@
+# Copyright 2021 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# TODO(flutter/flutter#85356): This file was originally generated by the
+# fuchsia.git script: `package_importer.py`. The generated `BUILD.gn` files were
+# copied to the flutter repo to support `dart_library` targets used for
+# Flutter-Fuchsia integration tests. This file can be maintained by hand, but it
+# would be better to implement a script for Flutter, to either generate these
+# BUILD.gn files or dynamically generate the GN targets.
+
+import("//flutter/tools/fuchsia/dart/dart_library.gni")
+
+dart_library("quiver") {
+  package_name = "quiver"
+
+  # The current version of this library is not null safe
+  language_version = "2.0"
+
+  deps = [
+    "//third_party/dart/pkg/meta",
+    "//third_party/dart/third_party/pkg/matcher",
+  ]
+
+  sources = [
+    "async.dart",
+    "cache.dart",
+    "check.dart",
+    "collection.dart",
+    "core.dart",
+    "io.dart",
+    "iterables.dart",
+    "mirrors.dart",
+    "pattern.dart",
+    "src/async/collect.dart",
+    "src/async/concat.dart",
+    "src/async/countdown_timer.dart",
+    "src/async/enumerate.dart",
+    "src/async/future_stream.dart",
+    "src/async/iteration.dart",
+    "src/async/metronome.dart",
+    "src/async/stream_buffer.dart",
+    "src/async/stream_router.dart",
+    "src/async/string.dart",
+    "src/cache/cache.dart",
+    "src/cache/map_cache.dart",
+    "src/collection/bimap.dart",
+    "src/collection/delegates/iterable.dart",
+    "src/collection/delegates/list.dart",
+    "src/collection/delegates/map.dart",
+    "src/collection/delegates/queue.dart",
+    "src/collection/delegates/set.dart",
+    "src/collection/lru_map.dart",
+    "src/collection/multimap.dart",
+    "src/collection/treeset.dart",
+    "src/core/hash.dart",
+    "src/core/optional.dart",
+    "src/iterables/concat.dart",
+    "src/iterables/count.dart",
+    "src/iterables/cycle.dart",
+    "src/iterables/enumerate.dart",
+    "src/iterables/generating_iterable.dart",
+    "src/iterables/infinite_iterable.dart",
+    "src/iterables/merge.dart",
+    "src/iterables/min_max.dart",
+    "src/iterables/partition.dart",
+    "src/iterables/range.dart",
+    "src/iterables/zip.dart",
+    "src/time/clock.dart",
+    "src/time/duration_unit_constants.dart",
+    "src/time/util.dart",
+    "strings.dart",
+    "testing/async.dart",
+    "testing/equality.dart",
+    "testing/runtime.dart",
+    "testing/src/async/fake_async.dart",
+    "testing/src/equality/equality.dart",
+    "testing/src/runtime/checked_mode.dart",
+    "testing/src/time/time.dart",
+    "testing/time.dart",
+    "time.dart",
+  ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/shaderc_flutter/BUILD.gn b/engine/src/flutter/build/secondary/third_party/shaderc_flutter/BUILD.gn
new file mode 100644
index 00000000000..ec41f7ac753
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/shaderc_flutter/BUILD.gn
@@ -0,0 +1,83 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+shaderc_base = "//third_party/shaderc"
+
+config("shaderc_util_config") {
+  include_dirs = [ "$shaderc_base/libshaderc_util/include/" ]
+}
+
+source_set("shaderc_util_flutter") {
+  public_configs = [ ":shaderc_util_config" ]
+
+  configs +=
+      [ "//third_party/vulkan-deps/spirv-tools/src:spvtools_public_config" ]
+
+  public_deps = [
+    "//third_party/vulkan-deps/glslang/src:glslang_sources",
+    "//third_party/vulkan-deps/spirv-tools/src:spvtools",
+  ]
+
+  defines = [ "ENABLE_HLSL=1" ]
+
+  if (is_clang) {
+    cflags_cc = [
+      "-Wno-deprecated-copy",
+      "-Wno-unknown-warning-option",
+    ]
+  }
+
+  sources = [
+    "$shaderc_base/libshaderc_util/include/libshaderc_util/counting_includer.h",
+    "$shaderc_base/libshaderc_util/include/libshaderc_util/exceptions.h",
+    "$shaderc_base/libshaderc_util/include/libshaderc_util/file_finder.h",
+    "$shaderc_base/libshaderc_util/include/libshaderc_util/format.h",
+    "$shaderc_base/libshaderc_util/include/libshaderc_util/io_shaderc.h",
+    "$shaderc_base/libshaderc_util/include/libshaderc_util/message.h",
+    "$shaderc_base/libshaderc_util/include/libshaderc_util/mutex.h",
+    "$shaderc_base/libshaderc_util/include/libshaderc_util/resources.h",
+    "$shaderc_base/libshaderc_util/include/libshaderc_util/spirv_tools_wrapper.h",
+    "$shaderc_base/libshaderc_util/include/libshaderc_util/string_piece.h",
+    "$shaderc_base/libshaderc_util/include/libshaderc_util/universal_unistd.h",
+    "$shaderc_base/libshaderc_util/include/libshaderc_util/version_profile.h",
+    "$shaderc_base/libshaderc_util/src/compiler.cc",
+    "$shaderc_base/libshaderc_util/src/file_finder.cc",
+    "$shaderc_base/libshaderc_util/src/io_shaderc.cc",
+    "$shaderc_base/libshaderc_util/src/message.cc",
+    "$shaderc_base/libshaderc_util/src/resources.cc",
+    "$shaderc_base/libshaderc_util/src/shader_stage.cc",
+    "$shaderc_base/libshaderc_util/src/spirv_tools_wrapper.cc",
+    "$shaderc_base/libshaderc_util/src/version_profile.cc",
+  ]
+}
+
+config("shaderc_config") {
+  include_dirs = [ "$shaderc_base/libshaderc/include/" ]
+}
+
+source_set("shaderc_flutter") {
+  defines = [ "SHADERC_IMPLEMENTATION" ]
+
+  public_configs = [ ":shaderc_config" ]
+
+  configs +=
+      [ "//third_party/vulkan-deps/spirv-tools/src:spvtools_public_config" ]
+
+  deps = [ ":shaderc_util_flutter" ]
+
+  public_deps = [
+    "//third_party/vulkan-deps/glslang/src:glslang_sources",
+    "//third_party/vulkan-deps/spirv-tools/src:spvtools",
+  ]
+
+  sources = [
+    "$shaderc_base/libshaderc/include/shaderc/env.h",
+    "$shaderc_base/libshaderc/include/shaderc/shaderc.h",
+    "$shaderc_base/libshaderc/include/shaderc/shaderc.hpp",
+    "$shaderc_base/libshaderc/include/shaderc/status.h",
+    "$shaderc_base/libshaderc/include/shaderc/visibility.h",
+    "$shaderc_base/libshaderc/src/shaderc.cc",
+    "$shaderc_base/libshaderc/src/shaderc_private.h",
+  ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/spirv_cross_flutter/BUILD.gn b/engine/src/flutter/build/secondary/third_party/spirv_cross_flutter/BUILD.gn
new file mode 100644
index 00000000000..2429fefe6be
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/spirv_cross_flutter/BUILD.gn
@@ -0,0 +1,41 @@
+# Copyright 2016 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+source_root = "//third_party/vulkan-deps/spirv-cross/src"
+
+config("spirv_cross_public") {
+  include_dirs = [ source_root ]
+
+  defines = [ "SPIRV_CROSS_EXCEPTIONS_TO_ASSERTIONS" ]
+}
+
+source_set("spirv_cross_flutter") {
+  public_configs = [ ":spirv_cross_public" ]
+
+  sources = [
+    "$source_root/GLSL.std.450.h",
+    "$source_root/spirv.hpp",
+    "$source_root/spirv_cfg.cpp",
+    "$source_root/spirv_cfg.hpp",
+    "$source_root/spirv_common.hpp",
+    "$source_root/spirv_cross.cpp",
+    "$source_root/spirv_cross.hpp",
+    "$source_root/spirv_cross_containers.hpp",
+    "$source_root/spirv_cross_error_handling.hpp",
+    "$source_root/spirv_cross_parsed_ir.cpp",
+    "$source_root/spirv_cross_parsed_ir.hpp",
+    "$source_root/spirv_cross_util.cpp",
+    "$source_root/spirv_cross_util.hpp",
+    "$source_root/spirv_glsl.cpp",
+    "$source_root/spirv_glsl.hpp",
+    "$source_root/spirv_hlsl.cpp",
+    "$source_root/spirv_hlsl.hpp",
+    "$source_root/spirv_msl.cpp",
+    "$source_root/spirv_msl.hpp",
+    "$source_root/spirv_parser.cpp",
+    "$source_root/spirv_parser.hpp",
+    "$source_root/spirv_reflect.cpp",
+    "$source_root/spirv_reflect.hpp",
+  ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/stb/BUILD.gn b/engine/src/flutter/build/secondary/third_party/stb/BUILD.gn
new file mode 100644
index 00000000000..68be14ffb5d
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/stb/BUILD.gn
@@ -0,0 +1,15 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+source_root = "//third_party/stb"
+
+source_set("stb_truetype") {
+  testonly = true
+
+  public = [ "$source_root/stb_truetype.h" ]
+
+  include_dirs = [ "$source_root" ]
+
+  sources = [ "//flutter/build/secondary/third_party/stb/stb_truetype_stub.cc" ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/stb/stb_truetype_stub.cc b/engine/src/flutter/build/secondary/third_party/stb/stb_truetype_stub.cc
new file mode 100644
index 00000000000..eaca9020be0
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/stb/stb_truetype_stub.cc
@@ -0,0 +1,6 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#define STB_TRUETYPE_IMPLEMENTATION
+#include "third_party/stb/stb_truetype.h"
diff --git a/engine/src/flutter/build/secondary/third_party/tinygltf/BUILD.gn b/engine/src/flutter/build/secondary/third_party/tinygltf/BUILD.gn
new file mode 100644
index 00000000000..d5f6b6cfff4
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/tinygltf/BUILD.gn
@@ -0,0 +1,23 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+source_root = "//third_party/tinygltf"
+
+source_set("tinygltf") {
+  public = [ "$source_root/tiny_gltf.h" ]
+
+  if (is_clang) {
+    cflags_cc = [ "-Wno-sign-compare" ]
+  }
+
+  include_dirs = [
+    "$source_root",
+    "$source_root/third_party/include",
+  ]
+
+  sources =
+      [ "//flutter/build/secondary/third_party/tinygltf/tinygltf_stub.cc" ]
+
+  deps = [ "//third_party/json" ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/tinygltf/tinygltf_stub.cc b/engine/src/flutter/build/secondary/third_party/tinygltf/tinygltf_stub.cc
new file mode 100644
index 00000000000..88e369d44f5
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/tinygltf/tinygltf_stub.cc
@@ -0,0 +1,11 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "nlohmann/json.hpp"
+
+#define TINYGLTF_IMPLEMENTATION
+#define TINYGLTF_NO_INCLUDE_JSON
+#define STB_IMAGE_IMPLEMENTATION
+#define STB_IMAGE_WRITE_IMPLEMENTATION
+#include "third_party/tinygltf/tiny_gltf.h"
diff --git a/engine/src/flutter/build/secondary/third_party/vulkan_memory_allocator/BUILD.gn b/engine/src/flutter/build/secondary/third_party/vulkan_memory_allocator/BUILD.gn
new file mode 100644
index 00000000000..8d4587d9130
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/vulkan_memory_allocator/BUILD.gn
@@ -0,0 +1,40 @@
+# Copyright 2020 The ANGLE Project Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+#
+# Custom GN integration for VulkanMemoryAllocator.
+
+declare_args() {
+  vma_vulkan_headers_dir = "//third_party/vulkan-deps/vulkan-headers/src"
+}
+
+config("vulkan_memory_allocator_config") {
+  include_dirs = [ "include" ]
+  if (is_clang) {
+    cflags_cc = [
+      "-Wno-c++98-compat-extra-semi",
+      "-Wno-deprecated-copy",
+      "-Wno-implicit-fallthrough",
+      "-Wno-nullability-completeness",
+      "-Wno-suggest-destructor-override",
+      "-Wno-suggest-override",
+      "-Wno-unused-private-field",
+      "-Wno-unused-variable",
+    ]
+  }
+  if (is_win && !is_clang) {
+    cflags_cc = [
+      "/wd4189",  # local variable is initialized but not referenced
+    ]
+  }
+  defines = [
+    "VMA_DYNAMIC_VULKAN_FUNCTIONS=0",
+    "VMA_STATIC_VULKAN_FUNCTIONS=0",
+  ]
+}
+
+source_set("vulkan_memory_allocator") {
+  sources = [ "include/vk_mem_alloc.h" ]
+  deps = [ "${vma_vulkan_headers_dir}:vulkan_headers" ]
+  public_configs = [ ":vulkan_memory_allocator_config" ]
+}
diff --git a/engine/src/flutter/build/secondary/third_party/vulkan_validation_layers/BUILD.gn b/engine/src/flutter/build/secondary/third_party/vulkan_validation_layers/BUILD.gn
new file mode 100644
index 00000000000..688ba45fda9
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/vulkan_validation_layers/BUILD.gn
@@ -0,0 +1,493 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+################################################################################
+# This is a temporary secondary build file until the rtti issue is solved
+# in vulkan-deps
+################################################################################
+
+import("//build_overrides/vulkan_validation_layers.gni")
+
+_checkout_dir = "//third_party/vulkan-deps/vulkan-validation-layers/src"
+
+vulkan_undefine_configs = []
+if (is_win) {
+  vulkan_undefine_configs += [ "//build/config/win:unicode" ]
+}
+
+vulkan_gen_dir = "$target_gen_dir/$vulkan_gen_subdir"
+raw_vulkan_gen_dir = rebase_path(vulkan_gen_dir, root_build_dir)
+
+vulkan_data_dir = "$root_out_dir/$vulkan_data_subdir"
+raw_vulkan_data_dir = rebase_path(vulkan_data_dir, root_build_dir)
+
+raw_root_out_dir = rebase_path(root_out_dir, root_build_dir)
+
+# This special action is needed to remove old VVL objects that are now renamed.
+action("vulkan_clean_old_validation_layer_objects") {
+  script = "$_checkout_dir/build-gn/remove_files.py"
+
+  # inputs is a (random) new file since the vvl roll, used to ensure the cleanup is done only once
+  inputs = [ "$_checkout_dir/layers/gpu_validation/gpu_validation.cpp" ]
+  outputs = [ "$vulkan_gen_dir/old_vvl_files_are_removed" ]
+  args = [
+    "$raw_vulkan_gen_dir/old_vvl_files_are_removed",
+    "$raw_root_out_dir/libVkLayer*",
+    "$raw_root_out_dir/VkLayer*",
+    "$raw_vulkan_data_dir/VkLayer*.json",
+  ]
+}
+
+config("generated_layers_config") {
+  if (is_clang) {
+    cflags = [
+      "-Wno-conversion",
+      "-Wno-deprecated-copy",
+      "-Wno-extra-semi",
+      "-Wno-implicit-fallthrough",
+      "-Wno-missing-field-initializers",
+      "-Wno-newline-eof",
+      "-Wno-sign-compare",
+      "-Wno-unused-const-variable",
+    ]
+  }
+}
+
+config("vulkan_internal_config") {
+  defines = [
+    "VULKAN_NON_CMAKE_BUILD",
+    "VK_ENABLE_BETA_EXTENSIONS",
+  ]
+
+  if (!is_win) {
+    cflags_cc = [ "-std=c++17" ]
+  } else {
+    cflags_cc = [ "/std:c++17" ]
+  }
+
+  cflags = []
+  if (is_clang || !is_win) {
+    cflags += [ "-Wno-unused-function" ]
+  }
+  if (is_clang && is_mac) {
+    cflags += [ "-Wno-unguarded-availability-new" ]
+  }
+  if (is_linux) {
+    defines += [
+      "SYSCONFDIR=\"/etc\"",
+      "FALLBACK_CONFIG_DIRS=\"/etc/xdg\"",
+      "FALLBACK_DATA_DIRS=\"/usr/local/share:/usr/share\"",
+    ]
+  }
+
+  # Suppress warnings the vulkan code doesn't comply with.
+  if (is_fuchsia) {
+    configs = [ "//build/config:Wno-unused-but-set-variable" ]
+  }
+  if (is_clang) {
+    cflags += [ "-Wno-extra-semi" ]
+  }
+}
+
+# The validation layers
+# ---------------------
+
+config("vulkan_layer_config") {
+  include_dirs = [
+    "$_checkout_dir/layers",
+    "$_checkout_dir/layers/external",
+    "$_checkout_dir/layers/generated",
+  ]
+  if (is_clang) {
+    cflags = [ "-Wno-extra-semi" ]
+  }
+}
+
+core_validation_sources = [
+  "$_checkout_dir/layers/containers/qfo_transfer.h",
+  "$_checkout_dir/layers/containers/range_vector.h",
+  "$_checkout_dir/layers/containers/subresource_adapter.cpp",
+  "$_checkout_dir/layers/containers/subresource_adapter.h",
+  "$_checkout_dir/layers/core_checks/cc_android.cpp",
+  "$_checkout_dir/layers/core_checks/cc_buffer.cpp",
+  "$_checkout_dir/layers/core_checks/cc_buffer_address.h",
+  "$_checkout_dir/layers/core_checks/cc_cmd_buffer.cpp",
+  "$_checkout_dir/layers/core_checks/cc_cmd_buffer_dynamic.cpp",
+  "$_checkout_dir/layers/core_checks/cc_copy_blit_resolve.cpp",
+  "$_checkout_dir/layers/core_checks/cc_descriptor.cpp",
+  "$_checkout_dir/layers/core_checks/cc_device.cpp",
+  "$_checkout_dir/layers/core_checks/cc_device_memory.cpp",
+  "$_checkout_dir/layers/core_checks/cc_drawdispatch.cpp",
+  "$_checkout_dir/layers/core_checks/cc_external_object.cpp",
+  "$_checkout_dir/layers/core_checks/cc_image.cpp",
+  "$_checkout_dir/layers/core_checks/cc_image_layout.cpp",
+  "$_checkout_dir/layers/core_checks/cc_pipeline.cpp",
+  "$_checkout_dir/layers/core_checks/cc_pipeline_compute.cpp",
+  "$_checkout_dir/layers/core_checks/cc_pipeline_graphics.cpp",
+  "$_checkout_dir/layers/core_checks/cc_pipeline_ray_tracing.cpp",
+  "$_checkout_dir/layers/core_checks/cc_query.cpp",
+  "$_checkout_dir/layers/core_checks/cc_queue.cpp",
+  "$_checkout_dir/layers/core_checks/cc_ray_tracing.cpp",
+  "$_checkout_dir/layers/core_checks/cc_render_pass.cpp",
+  "$_checkout_dir/layers/core_checks/cc_shader.cpp",
+  "$_checkout_dir/layers/core_checks/cc_shader.h",
+  "$_checkout_dir/layers/core_checks/cc_synchronization.cpp",
+  "$_checkout_dir/layers/core_checks/cc_video.cpp",
+  "$_checkout_dir/layers/core_checks/cc_wsi.cpp",
+  "$_checkout_dir/layers/core_checks/cc_ycbcr.cpp",
+  "$_checkout_dir/layers/core_checks/core_validation.h",
+  "$_checkout_dir/layers/error_message/core_error_location.cpp",
+  "$_checkout_dir/layers/error_message/core_error_location.h",
+  "$_checkout_dir/layers/error_message/validation_error_enums.h",
+  "$_checkout_dir/layers/external/vma/vk_mem_alloc.h",
+  "$_checkout_dir/layers/external/vma/vma.cpp",
+  "$_checkout_dir/layers/external/vma/vma.h",
+  "$_checkout_dir/layers/generated/command_validation.cpp",
+  "$_checkout_dir/layers/generated/command_validation.h",
+  "$_checkout_dir/layers/generated/gpu_as_inspection_comp.h",
+  "$_checkout_dir/layers/generated/gpu_pre_dispatch_comp.h",
+  "$_checkout_dir/layers/generated/gpu_pre_draw_vert.h",
+  "$_checkout_dir/layers/generated/spirv_grammar_helper.cpp",
+  "$_checkout_dir/layers/generated/spirv_grammar_helper.h",
+  "$_checkout_dir/layers/generated/spirv_validation_helper.cpp",
+  "$_checkout_dir/layers/generated/sync_validation_types.cpp",
+  "$_checkout_dir/layers/generated/sync_validation_types.h",
+  "$_checkout_dir/layers/gpu_shaders/gpu_shaders_constants.h",
+  "$_checkout_dir/layers/gpu_validation/gpu_utils.cpp",
+  "$_checkout_dir/layers/gpu_validation/gpu_utils.h",
+  "$_checkout_dir/layers/gpu_validation/gpu_validation.cpp",
+  "$_checkout_dir/layers/gpu_validation/gpu_validation.h",
+  "$_checkout_dir/layers/gpu_validation/gpu_vuids.h",
+  "$_checkout_dir/layers/state_tracker/base_node.cpp",
+  "$_checkout_dir/layers/state_tracker/base_node.h",
+  "$_checkout_dir/layers/state_tracker/buffer_state.cpp",
+  "$_checkout_dir/layers/state_tracker/buffer_state.h",
+  "$_checkout_dir/layers/state_tracker/cmd_buffer_state.cpp",
+  "$_checkout_dir/layers/state_tracker/cmd_buffer_state.h",
+  "$_checkout_dir/layers/state_tracker/descriptor_sets.cpp",
+  "$_checkout_dir/layers/state_tracker/descriptor_sets.h",
+  "$_checkout_dir/layers/state_tracker/device_memory_state.cpp",
+  "$_checkout_dir/layers/state_tracker/device_memory_state.h",
+  "$_checkout_dir/layers/state_tracker/device_state.h",
+  "$_checkout_dir/layers/state_tracker/image_layout_map.cpp",
+  "$_checkout_dir/layers/state_tracker/image_layout_map.h",
+  "$_checkout_dir/layers/state_tracker/image_state.cpp",
+  "$_checkout_dir/layers/state_tracker/image_state.h",
+  "$_checkout_dir/layers/state_tracker/pipeline_layout_state.cpp",
+  "$_checkout_dir/layers/state_tracker/pipeline_layout_state.h",
+  "$_checkout_dir/layers/state_tracker/pipeline_state.cpp",
+  "$_checkout_dir/layers/state_tracker/pipeline_state.h",
+  "$_checkout_dir/layers/state_tracker/pipeline_sub_state.cpp",
+  "$_checkout_dir/layers/state_tracker/pipeline_sub_state.h",
+  "$_checkout_dir/layers/state_tracker/query_state.h",
+  "$_checkout_dir/layers/state_tracker/queue_state.cpp",
+  "$_checkout_dir/layers/state_tracker/queue_state.h",
+  "$_checkout_dir/layers/state_tracker/ray_tracing_state.h",
+  "$_checkout_dir/layers/state_tracker/render_pass_state.cpp",
+  "$_checkout_dir/layers/state_tracker/render_pass_state.h",
+  "$_checkout_dir/layers/state_tracker/sampler_state.h",
+  "$_checkout_dir/layers/state_tracker/shader_instruction.cpp",
+  "$_checkout_dir/layers/state_tracker/shader_instruction.h",
+  "$_checkout_dir/layers/state_tracker/shader_module.cpp",
+  "$_checkout_dir/layers/state_tracker/shader_module.h",
+  "$_checkout_dir/layers/state_tracker/state_tracker.cpp",
+  "$_checkout_dir/layers/state_tracker/state_tracker.h",
+  "$_checkout_dir/layers/state_tracker/video_session_state.cpp",
+  "$_checkout_dir/layers/state_tracker/video_session_state.h",
+  "$_checkout_dir/layers/sync/sync_utils.cpp",
+  "$_checkout_dir/layers/sync/sync_utils.h",
+  "$_checkout_dir/layers/sync/sync_validation.cpp",
+  "$_checkout_dir/layers/sync/sync_validation.h",
+  "$_checkout_dir/layers/sync/sync_vuid_maps.cpp",
+  "$_checkout_dir/layers/sync/sync_vuid_maps.h",
+  "$_checkout_dir/layers/utils/android_ndk_types.h",
+  "$_checkout_dir/layers/utils/convert_to_renderpass2.cpp",
+  "$_checkout_dir/layers/utils/convert_to_renderpass2.h",
+]
+
+object_lifetimes_sources = [
+  "$_checkout_dir/layers/generated/object_tracker.cpp",
+  "$_checkout_dir/layers/generated/object_tracker.h",
+  "$_checkout_dir/layers/object_tracker/object_lifetime_validation.h",
+  "$_checkout_dir/layers/object_tracker/object_tracker_utils.cpp",
+]
+
+stateless_validation_sources = [
+  "$_checkout_dir/layers/generated/enum_flag_bits.h",
+  "$_checkout_dir/layers/generated/parameter_validation.cpp",
+  "$_checkout_dir/layers/generated/parameter_validation.h",
+  "$_checkout_dir/layers/stateless/parameter_name.h",
+  "$_checkout_dir/layers/stateless/sl_buffer.cpp",
+  "$_checkout_dir/layers/stateless/sl_cmd_buffer.cpp",
+  "$_checkout_dir/layers/stateless/sl_cmd_buffer_dynamic.cpp",
+  "$_checkout_dir/layers/stateless/sl_descriptor.cpp",
+  "$_checkout_dir/layers/stateless/sl_device_memory.cpp",
+  "$_checkout_dir/layers/stateless/sl_external_object.cpp",
+  "$_checkout_dir/layers/stateless/sl_framebuffer.cpp",
+  "$_checkout_dir/layers/stateless/sl_image.cpp",
+  "$_checkout_dir/layers/stateless/sl_instance_device.cpp",
+  "$_checkout_dir/layers/stateless/sl_pipeline.cpp",
+  "$_checkout_dir/layers/stateless/sl_ray_tracing.cpp",
+  "$_checkout_dir/layers/stateless/sl_render_pass.cpp",
+  "$_checkout_dir/layers/stateless/sl_synchronization.cpp",
+  "$_checkout_dir/layers/stateless/sl_wsi.cpp",
+  "$_checkout_dir/layers/stateless/stateless_validation.h",
+]
+
+thread_safety_sources = [
+  "$_checkout_dir/layers/generated/thread_safety.cpp",
+  "$_checkout_dir/layers/generated/thread_safety.h",
+]
+
+unique_objects_sources = []
+
+best_practices_sources = [
+  "$_checkout_dir/layers/best_practices/best_practices_error_enums.h",
+  "$_checkout_dir/layers/best_practices/best_practices_utils.cpp",
+  "$_checkout_dir/layers/best_practices/best_practices_validation.h",
+  "$_checkout_dir/layers/best_practices/bp_buffer.cpp",
+  "$_checkout_dir/layers/best_practices/bp_cmd_buffer.cpp",
+  "$_checkout_dir/layers/best_practices/bp_copy_blit_resolve.cpp",
+  "$_checkout_dir/layers/best_practices/bp_descriptor.cpp",
+  "$_checkout_dir/layers/best_practices/bp_device_memory.cpp",
+  "$_checkout_dir/layers/best_practices/bp_drawdispatch.cpp",
+  "$_checkout_dir/layers/best_practices/bp_framebuffer.cpp",
+  "$_checkout_dir/layers/best_practices/bp_image.cpp",
+  "$_checkout_dir/layers/best_practices/bp_instance_device.cpp",
+  "$_checkout_dir/layers/best_practices/bp_pipeline.cpp",
+  "$_checkout_dir/layers/best_practices/bp_ray_tracing.cpp",
+  "$_checkout_dir/layers/best_practices/bp_render_pass.cpp",
+  "$_checkout_dir/layers/best_practices/bp_synchronization.cpp",
+  "$_checkout_dir/layers/best_practices/bp_video.cpp",
+  "$_checkout_dir/layers/best_practices/bp_wsi.cpp",
+  "$_checkout_dir/layers/generated/best_practices.cpp",
+  "$_checkout_dir/layers/generated/best_practices.h",
+]
+
+debug_printf_sources = [
+  "$_checkout_dir/layers/gpu_validation/debug_printf.cpp",
+  "$_checkout_dir/layers/gpu_validation/debug_printf.h",
+]
+
+chassis_sources = [
+  "$_checkout_dir/layers/generated/chassis.cpp",
+  "$_checkout_dir/layers/generated/chassis.h",
+  "$_checkout_dir/layers/generated/chassis_dispatch_helper.h",
+  "$_checkout_dir/layers/generated/layer_chassis_dispatch.cpp",
+  "$_checkout_dir/layers/generated/layer_chassis_dispatch.h",
+  "$_checkout_dir/layers/generated/valid_param_values.cpp",
+  "$_checkout_dir/layers/generated/valid_param_values.h",
+  "$_checkout_dir/layers/generated/vk_dispatch_table_helper.h",
+  "$_checkout_dir/layers/generated/vk_extension_helper.h",
+  "$_checkout_dir/layers/generated/vk_safe_struct.cpp",
+  "$_checkout_dir/layers/layer_options.cpp",
+  "$_checkout_dir/layers/layer_options.h",
+  "$_checkout_dir/layers/vk_layer_settings_ext.h",
+  "$vulkan_headers_dir/include/vulkan/vk_layer.h",
+  "$vulkan_headers_dir/include/vulkan/vulkan.h",
+]
+
+layers = [ [
+      "khronos_validation",
+      core_validation_sources + object_lifetimes_sources +
+          stateless_validation_sources + thread_safety_sources +
+          unique_objects_sources + best_practices_sources +
+          debug_printf_sources + chassis_sources,
+      [ ":vulkan_core_validation_glslang" ],
+      [],
+    ] ]
+
+if (!is_android) {
+  action("vulkan_gen_json_files") {
+    script = "$_checkout_dir/build-gn/generate_vulkan_layers_json.py"
+
+    deps = [ "$vulkan_headers_dir:vulkan_headers" ]
+    if (!is_fuchsia) {
+      # Make sure that the cleanup of old layer JSON files happens before the new ones are generated.
+      deps += [ ":vulkan_clean_old_validation_layer_objects" ]
+    }
+
+    sources = [ "$_checkout_dir/layers/VkLayer_khronos_validation.json.in" ]
+    outputs = [ "$vulkan_data_dir/VkLayer_khronos_validation.json" ]
+
+    if (is_linux) {
+      _platform = "Linux"
+    } else if (is_win) {
+      _platform = "Windows"
+    } else if (is_mac) {
+      _platform = "Darwin"
+    } else if (is_fuchsia) {
+      _platform = "Fuchsia"
+    } else {
+      _platform = "Other"
+    }
+
+    args = [
+             "--platform",
+             _platform,
+             rebase_path("$_checkout_dir/layers/", root_build_dir),
+             rebase_path(vulkan_data_dir, root_build_dir),
+           ] + rebase_path(sources, root_build_dir)
+    if (is_fuchsia) {
+      args += [ "--no-path-prefix" ]
+    }
+
+    # The layer JSON files are part of the necessary data deps.
+    data = outputs
+  }
+}
+
+config("vulkan_memory_allocator_config") {
+  if (is_clang) {
+    cflags_cc = [ "-Wno-nullability-completeness" ]
+  }
+}
+
+source_set("vulkan_layer_utils") {
+  include_dirs = [
+    "$_checkout_dir/layers",
+    "$_checkout_dir/layers/external",
+    "$_checkout_dir/layers/generated",
+  ]
+  sources = [
+    "$_checkout_dir/layers/containers/custom_containers.h",
+    "$_checkout_dir/layers/containers/sparse_containers.h",
+    "$_checkout_dir/layers/error_message/logging.cpp",
+    "$_checkout_dir/layers/error_message/logging.h",
+    "$_checkout_dir/layers/external/xxhash.cpp",
+    "$_checkout_dir/layers/external/xxhash.h",
+    "$_checkout_dir/layers/generated/vk_enum_string_helper.h",
+    "$_checkout_dir/layers/generated/vk_extension_helper.h",
+    "$_checkout_dir/layers/generated/vk_format_utils.cpp",
+    "$_checkout_dir/layers/generated/vk_format_utils.h",
+    "$_checkout_dir/layers/generated/vk_layer_dispatch_table.h",
+    "$_checkout_dir/layers/generated/vk_object_types.h",
+    "$_checkout_dir/layers/generated/vk_safe_struct.h",
+    "$_checkout_dir/layers/generated/vk_typemap_helper.h",
+    "$_checkout_dir/layers/generated/vk_validation_error_messages.h",
+    "$_checkout_dir/layers/utils/android_ndk_types.h",
+    "$_checkout_dir/layers/utils/cast_utils.h",
+    "$_checkout_dir/layers/utils/hash_util.h",
+    "$_checkout_dir/layers/utils/hash_vk_types.h",
+    "$_checkout_dir/layers/utils/vk_layer_extension_utils.cpp",
+    "$_checkout_dir/layers/utils/vk_layer_extension_utils.h",
+    "$_checkout_dir/layers/utils/vk_layer_utils.cpp",
+    "$_checkout_dir/layers/utils/vk_layer_utils.h",
+    "$_checkout_dir/layers/vk_layer_config.cpp",
+    "$_checkout_dir/layers/vk_layer_config.h",
+    "$vulkan_headers_dir/include/vulkan/vk_layer.h",
+    "$vulkan_headers_dir/include/vulkan/vulkan.h",
+  ]
+  defines = [ "XXH_NO_LONG_LONG" ]
+  public_configs = [
+    ":vulkan_internal_config",
+    ":vulkan_memory_allocator_config",
+  ]
+  public_deps = [ "$vulkan_headers_dir:vulkan_headers" ]
+
+  configs -= vulkan_undefine_configs
+  if (!is_fuchsia) {
+    configs -= [ "//build/config/compiler:chromium_code" ]
+    configs += [ "//build/config/compiler:no_chromium_code" ]
+  }
+}
+
+config("vulkan_core_validation_config") {
+  include_dirs = [ "$vvl_glslang_dir" ]
+}
+
+source_set("vulkan_core_validation_glslang") {
+  public_deps = [
+    "${vvl_spirv_tools_dir}:spvtools",
+    "${vvl_spirv_tools_dir}:spvtools_opt",
+    "${vvl_spirv_tools_dir}:spvtools_val",
+  ]
+  public_configs = [
+    "$vulkan_headers_dir:vulkan_headers_config",
+    ":vulkan_core_validation_config",
+  ]
+}
+
+config("vulkan_stateless_validation_config") {
+  if (is_clang) {
+    cflags_cc = [ "-Wno-unused-const-variable" ]
+  }
+}
+
+if (is_fuchsia) {
+  library_type = "loadable_module"
+} else {
+  library_type = "shared_library"
+}
+
+foreach(layer_info, layers) {
+  name = layer_info[0]
+  target(library_type, "VkLayer_$name") {
+    defines = []
+    ldflags = []
+    if (is_fuchsia) {
+      configs -= [ "//build/config:thread_safety_annotations" ]
+      ldflags += [ "-static-libstdc++" ]
+      configs += [ "//build/config:rtti" ]
+    } else {
+      configs -= [ "//build/config/compiler:chromium_code" ]
+      configs += [ "//build/config/compiler:no_chromium_code" ]
+
+      # The following line is what has to change to fix chromium compilation.
+      configs -= [ "//build/config/compiler:no_rtti" ]
+      configs += [ "//build/config/compiler:rtti" ]
+    }
+    configs -= vulkan_undefine_configs
+    configs += [ ":generated_layers_config" ]
+    public_configs = [ ":vulkan_layer_config" ]
+    deps = [ ":vulkan_layer_utils" ]
+    if (!is_fuchsia) {
+      deps += [
+        # Make sure the cleanup of old layers happen before the new ones are compiled.
+        ":vulkan_clean_old_validation_layer_objects",
+      ]
+    }
+    if (layer_info[2] != "") {
+      deps += layer_info[2]
+    }
+    sources = layer_info[1]
+    if (is_win) {
+      defines += [ "NOMINMAX" ]
+      sources += [ "$_checkout_dir/layers/VkLayer_$name.def" ]
+    }
+    if (is_linux || is_android || is_fuchsia) {
+      ldflags += [ "-Wl,-Bsymbolic,--exclude-libs,ALL" ]
+    }
+    if (defined(ozone_platform_x11) && ozone_platform_x11) {
+      defines += [ "VK_USE_PLATFORM_XLIB_KHR" ]
+    }
+    if (is_android) {
+      libs = [
+        "c++",  # Note: C++ added by Flutter.
+        "log",
+        "nativewindow",
+      ]
+      # Note: config edit removed by Flutter
+      # configs -= [ "//build/config/android:hide_all_but_jni_onload" ]
+    }
+    defines += layer_info[3]
+  }
+}
+
+group("vulkan_validation_layers") {
+  public_deps = []
+  data_deps = []
+  foreach(layer_info, layers) {
+    name = layer_info[0]
+    if (is_fuchsia) {
+      public_deps += [ ":VkLayer_$name" ]
+    } else {
+      data_deps += [ ":VkLayer_$name" ]
+    }
+  }
+}
+
+group("tests") {
+  # TODO(fxbug.dev/13288)
+}
diff --git a/engine/src/flutter/build/secondary/third_party/wuffs/BUILD.gn b/engine/src/flutter/build/secondary/third_party/wuffs/BUILD.gn
new file mode 100644
index 00000000000..a78200b1e8f
--- /dev/null
+++ b/engine/src/flutter/build/secondary/third_party/wuffs/BUILD.gn
@@ -0,0 +1,59 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+config("wuffs_public") {
+  include_dirs = [ "release/c" ]
+
+  cflags = []
+
+  if (is_clang) {
+    cflags += [
+      "-Wno-unused-function",
+      "-Wno-c++11-narrowing",
+    ]
+  }
+}
+
+source_set("wuffs") {
+  public_configs = [ ":wuffs_public" ]
+
+  defines = [
+    # Copy/pasting from "../externals/wuffs/release/c/wuffs-*.c":
+    #
+    # ----
+    #
+    # Wuffs ships as a "single file C library" or "header file library" as per
+    # https://github.com/nothings/stb/blob/master/docs/stb_howto.txt
+    #
+    # To use that single file as a "foo.c"-like implementation, instead of a
+    # "foo.h"-like header, #define WUFFS_IMPLEMENTATION before #include'ing or
+    # compiling it.
+    #
+    # ----
+    "WUFFS_IMPLEMENTATION",
+
+    # Continuing to copy/paste:
+    #
+    # ----
+    #
+    # Defining the WUFFS_CONFIG__MODULE* macros are optional, but it lets users
+    # of Wuffs' .c file explicitly include which parts of Wuffs to build. That
+    # file contains the entire Wuffs standard library, implementing a variety of
+    # codecs and file formats. Without this macro definition, an optimizing
+    # compiler or linker may very well discard Wuffs code for unused codecs,
+    # but listing the Wuffs modules we use makes that process explicit.
+    # Preprocessing means that such code simply isn't compiled.
+    #
+    # ----
+    #
+    # For Skia, we're only interested in particular image codes (e.g. GIF) and
+    # their dependencies (e.g. BASE, LZW).
+    "WUFFS_CONFIG__MODULES",
+    "WUFFS_CONFIG__MODULE__BASE",
+    "WUFFS_CONFIG__MODULE__GIF",
+    "WUFFS_CONFIG__MODULE__LZW",
+  ]
+
+  sources = [ "release/c/wuffs-v0.3.c" ]
+}
diff --git a/engine/src/flutter/ci/pylint.sh b/engine/src/flutter/ci/pylint.sh
index a3e3422152b..e94f5248cb8 100755
--- a/engine/src/flutter/ci/pylint.sh
+++ b/engine/src/flutter/ci/pylint.sh
@@ -34,7 +34,6 @@ echo "$(date +%T) Running pylint"
 
 cd "$FLUTTER_DIR"
 pylint-2.7 --rcfile=.pylintrc \
-  "build/" \
   "ci/" \
   "impeller/" \
   "sky/" \