Provide a stub platform view embedder for tester to avoid emitting errors (flutter/engine#25661)

engine/src/flutter/lib/ui/painting/image_decoder.cc

@@ -286,7 +286,7 @@ void ImageDecoder::Decode(fml::RefPtr<ImageDescriptor> descriptor_ref_ptr,
                                                             flow);
 
         if (!decompressed) {
-          FML_LOG(ERROR) << "Could not decompress image.";
+          FML_DLOG(ERROR) << "Could not decompress image.";
           result({}, std::move(flow));
           return;
         }
@@ -298,7 +298,7 @@ void ImageDecoder::Decode(fml::RefPtr<ImageDescriptor> descriptor_ref_ptr,
                                                flow =
                                                    std::move(flow)]() mutable {
           if (!io_manager) {
-            FML_LOG(ERROR) << "Could not acquire IO manager.";
+            FML_DLOG(ERROR) << "Could not acquire IO manager.";
             result({}, std::move(flow));
             return;
           }
@@ -316,7 +316,7 @@ void ImageDecoder::Decode(fml::RefPtr<ImageDescriptor> descriptor_ref_ptr,
               UploadRasterImage(std::move(decompressed), io_manager, flow);
 
           if (!uploaded.get()) {
-            FML_LOG(ERROR) << "Could not upload image to the GPU.";
+            FML_DLOG(ERROR) << "Could not upload image to the GPU.";
             result({}, std::move(flow));
             return;
           }

engine/src/flutter/lib/ui/painting/image_descriptor.cc

@@ -171,14 +171,14 @@ void ImageDescriptor::instantiateCodec(Dart_Handle codec_handle,
 sk_sp<SkImage> ImageDescriptor::image() const {
   SkBitmap bitmap;
   if (!bitmap.tryAllocPixels(image_info_)) {
-    FML_LOG(ERROR) << "Failed to allocate memory for bitmap of size "
-                   << image_info_.computeMinByteSize() << "B";
+    FML_DLOG(ERROR) << "Failed to allocate memory for bitmap of size "
+                    << image_info_.computeMinByteSize() << "B";
     return nullptr;
   }
 
   const auto& pixmap = bitmap.pixmap();
   if (!get_pixels(pixmap)) {
-    FML_LOG(ERROR) << "Failed to get pixels for image.";
+    FML_DLOG(ERROR) << "Failed to get pixels for image.";
     return nullptr;
   }
   bitmap.setImmutable();

engine/src/flutter/shell/testing/BUILD.gn

@@ -25,6 +25,7 @@ executable("testing") {
   deps = [
     "//flutter/assets",
     "//flutter/common",
+    "//flutter/flow",
     "//flutter/fml",
     "//flutter/lib/snapshot",
     "//flutter/shell/common",

engine/src/flutter/shell/testing/tester_main.cc

@@ -10,6 +10,7 @@
 
 #include "flutter/assets/asset_manager.h"
 #include "flutter/assets/directory_asset_bundle.h"
+#include "flutter/flow/embedded_views.h"
 #include "flutter/fml/build_config.h"
 #include "flutter/fml/file.h"
 #include "flutter/fml/make_copyable.h"
@@ -32,6 +33,32 @@
 
 namespace flutter {
 
+class TesterExternalViewEmbedder : public ExternalViewEmbedder {
+  // |ExternalViewEmbedder|
+  SkCanvas* GetRootCanvas() override { return nullptr; }
+
+  // |ExternalViewEmbedder|
+  void CancelFrame() override {}
+
+  // |ExternalViewEmbedder|
+  void BeginFrame(
+      SkISize frame_size,
+      GrDirectContext* context,
+      double device_pixel_ratio,
+      fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) override {}
+
+  // |ExternalViewEmbedder|
+  void PrerollCompositeEmbeddedView(
+      int view_id,
+      std::unique_ptr<EmbeddedViewParams> params) override {}
+
+  // |ExternalViewEmbedder|
+  std::vector<SkCanvas*> GetCurrentCanvases() override { return {}; }
+
+  // |ExternalViewEmbedder|
+  SkCanvas* CompositeEmbeddedView(int view_id) override { return nullptr; }
+};
+
 class TesterPlatformView : public PlatformView,
                            public GPUSurfaceSoftwareDelegate {
  public:
@@ -73,8 +100,15 @@ class TesterPlatformView : public PlatformView,
     return true;
   }
 
+  // |PlatformView|
+  std::shared_ptr<ExternalViewEmbedder> CreateExternalViewEmbedder() override {
+    return external_view_embedder_;
+  }
+
  private:
   sk_sp<SkSurface> sk_surface_ = nullptr;
+  std::shared_ptr<TesterExternalViewEmbedder> external_view_embedder_ =
+      std::make_shared<TesterExternalViewEmbedder>();
 };
 
 // Checks whether the engine's main Dart isolate has no pending work.  If so,

engine/src/flutter/testing/dart/platform_view_test.dart

@@ -0,0 +1,19 @@
+// 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 'dart:ui';
+
+import 'package:test/test.dart';
+
+void main() {
+  test('PlatformView layers do not emit errors from tester', () async {
+    final SceneBuilder builder = SceneBuilder();
+    builder.addPlatformView(1);
+    final Scene scene = builder.build();
+
+    window.render(scene);
+    scene.dispose();
+    // Test harness asserts that this does not emit an error from the shell logs.
+  });
+}

engine/src/flutter/testing/run_tests.py

@@ -31,21 +31,31 @@ def PrintDivider(char='='):
     print(''.join([char for _ in xrange(80)]))
   print '\n'
 
-def RunCmd(cmd, **kwargs):
+def RunCmd(cmd, forbidden_output=[], **kwargs):
   command_string = ' '.join(cmd)
 
   PrintDivider('>')
   print 'Running command "%s"' % command_string
 
   start_time = time.time()
-  process = subprocess.Popen(cmd, stdout=sys.stdout, stderr=sys.stderr, **kwargs)
-  process.communicate()
+  stdout_pipe = sys.stdout if not forbidden_output else subprocess.PIPE
+  stderr_pipe = sys.stderr if not forbidden_output else subprocess.PIPE
+  process = subprocess.Popen(cmd, stdout=stdout_pipe, stderr=stderr_pipe, **kwargs)
+  stdout, stderr = process.communicate()
   end_time = time.time()
 
   if process.returncode != 0:
     PrintDivider('!')
     raise Exception('Command "%s" exited with code %d' % (command_string, process.returncode))
 
+  if stdout or stderr:
+    print(stdout)
+    print(stderr)
+
+  for forbidden_string in forbidden_output:
+    if (stdout and forbidden_string in stdout) or (stderr and forbidden_string in stderr):
+      raise Exception('command "%s" contained forbidden string %s' % (command_string, forbidden_string))
+
   PrintDivider('<')
   print 'Command run successfully in %.2f seconds: %s' % (end_time - start_time, command_string)
 
@@ -81,7 +91,7 @@ def FindExecutablePath(path):
   raise Exception('Executable %s does not exist!' % path)
 
 
-def RunEngineExecutable(build_dir, executable_name, filter, flags=[], cwd=buildroot_dir):
+def RunEngineExecutable(build_dir, executable_name, filter, flags=[], cwd=buildroot_dir, forbidden_output=[]):
   if filter is not None and executable_name not in filter:
     print('Skipping %s due to filter.' % executable_name)
     return
@@ -91,7 +101,7 @@ def RunEngineExecutable(build_dir, executable_name, filter, flags=[], cwd=buildr
   print('Running %s in %s' % (executable_name, cwd))
   test_command = [ executable ] + flags
   print(' '.join(test_command))
-  RunCmd(test_command, cwd=cwd)
+  RunCmd(test_command, cwd=cwd, forbidden_output=forbidden_output)
 
 
 def RunCCTests(build_dir, filter):
@@ -247,7 +257,8 @@ def RunDartTest(build_dir, dart_file, verbose_dart_snapshot, multithreaded, enab
     threading = 'single-threaded'
 
   print("Running test '%s' using 'flutter_tester' (%s)" % (kernel_file_name, threading))
-  RunEngineExecutable(build_dir, 'flutter_tester', None, command_args)
+  forbidden_output = [] if 'unopt' in build_dir else ['[ERROR']
+  RunEngineExecutable(build_dir, 'flutter_tester', None, command_args, forbidden_output=forbidden_output)
 
 def RunPubGet(build_dir, directory):
   print("Running 'pub get' in the tests directory %s" % dart_tests_dir)
@@ -263,7 +274,7 @@ def EnsureDebugUnoptSkyPackagesAreBuilt():
   variant_out_dir = os.path.join(out_dir, 'host_debug_unopt')
 
   ninja_command = [
-    'autoninja',
+    'ninja',
     '-C',
     variant_out_dir,
     'flutter/sky/packages'