Fix embedder_->EndFrame() not called in case of DrawLastLayerTree() (flutter/engine#29979)

engine/src/flutter/shell/common/rasterizer.cc

@@ -147,7 +147,15 @@ void Rasterizer::DrawLastLayerTree(
   if (!last_layer_tree_ || !surface_) {
     return;
   }
-  DrawToSurface(*frame_timings_recorder, *last_layer_tree_);
+  RasterStatus raster_status =
+      DrawToSurface(*frame_timings_recorder, *last_layer_tree_);
+
+  // EndFrame should perform cleanups for the external_view_embedder.
+  if (external_view_embedder_) {
+    bool should_resubmit_frame = ShouldResubmitFrame(raster_status);
+    external_view_embedder_->EndFrame(should_resubmit_frame,
+                                      raster_thread_merger_);
+  }
 }
 
 RasterStatus Rasterizer::Draw(
@@ -184,8 +192,7 @@ RasterStatus Rasterizer::Draw(
   // if the raster status is to resubmit the frame, we push the frame to the
   // front of the queue and also change the consume status to more available.
 
-  auto should_resubmit_frame = raster_status == RasterStatus::kResubmit ||
-                               raster_status == RasterStatus::kSkipAndRetry;
+  bool should_resubmit_frame = ShouldResubmitFrame(raster_status);
   if (should_resubmit_frame) {
     auto front_continuation = pipeline->ProduceIfEmpty();
     bool result =
@@ -226,6 +233,11 @@ RasterStatus Rasterizer::Draw(
   return raster_status;
 }
 
+bool Rasterizer::ShouldResubmitFrame(const RasterStatus& raster_status) {
+  return raster_status == RasterStatus::kResubmit ||
+         raster_status == RasterStatus::kSkipAndRetry;
+}
+
 namespace {
 sk_sp<SkImage> DrawSnapshot(
     sk_sp<SkSurface> surface,
@@ -387,8 +399,7 @@ RasterStatus Rasterizer::DoDraw(
       DrawToSurface(*frame_timings_recorder, *layer_tree);
   if (raster_status == RasterStatus::kSuccess) {
     last_layer_tree_ = std::move(layer_tree);
-  } else if (raster_status == RasterStatus::kResubmit ||
-             raster_status == RasterStatus::kSkipAndRetry) {
+  } else if (ShouldResubmitFrame(raster_status)) {
     resubmitted_layer_tree_ = std::move(layer_tree);
     return raster_status;
   } else if (raster_status == RasterStatus::kDiscarded) {

engine/src/flutter/shell/common/rasterizer.h

@@ -483,6 +483,7 @@ class Rasterizer final : public SnapshotDelegate {
   void FireNextFrameCallbackIfPresent();
 
   static bool NoDiscard(const flutter::LayerTree& layer_tree) { return false; }
+  static bool ShouldResubmitFrame(const RasterStatus& raster_status);
 
   Delegate& delegate_;
   std::unique_ptr<Surface> surface_;

engine/src/flutter/shell/common/rasterizer_unittests.cc

@@ -300,6 +300,80 @@ TEST(
   rasterizer->Draw(CreateFinishedBuildRecorder(), pipeline, no_discard);
 }
 
+TEST(RasterizerTest,
+     drawLastLayerTreeWithThreadsMergedExternalViewEmbedderAndEndFrameCalled) {
+  std::string test_name =
+      ::testing::UnitTest::GetInstance()->current_test_info()->name();
+  ThreadHost thread_host("io.flutter.test." + test_name + ".",
+                         ThreadHost::Type::Platform | ThreadHost::Type::RASTER |
+                             ThreadHost::Type::IO | ThreadHost::Type::UI);
+  fml::MessageLoop::EnsureInitializedForCurrentThread();
+  TaskRunners task_runners("test",
+                           fml::MessageLoop::GetCurrent().GetTaskRunner(),
+                           fml::MessageLoop::GetCurrent().GetTaskRunner(),
+                           thread_host.ui_thread->GetTaskRunner(),
+                           thread_host.io_thread->GetTaskRunner());
+
+  MockDelegate delegate;
+  EXPECT_CALL(delegate, GetTaskRunners())
+      .WillRepeatedly(ReturnRef(task_runners));
+  EXPECT_CALL(delegate, OnFrameRasterized(_));
+
+  auto rasterizer = std::make_unique<Rasterizer>(delegate);
+  auto surface = std::make_unique<MockSurface>();
+
+  std::shared_ptr<MockExternalViewEmbedder> external_view_embedder =
+      std::make_shared<MockExternalViewEmbedder>();
+  rasterizer->SetExternalViewEmbedder(external_view_embedder);
+
+  SurfaceFrame::FramebufferInfo framebuffer_info;
+  framebuffer_info.supports_readback = true;
+
+  auto surface_frame1 = std::make_unique<SurfaceFrame>(
+      /*surface=*/nullptr, framebuffer_info,
+      /*submit_callback=*/[](const SurfaceFrame&, SkCanvas*) { return true; });
+  auto surface_frame2 = std::make_unique<SurfaceFrame>(
+      /*surface=*/nullptr, framebuffer_info,
+      /*submit_callback=*/[](const SurfaceFrame&, SkCanvas*) { return true; });
+  EXPECT_CALL(*surface, AllowsDrawingWhenGpuDisabled())
+      .WillRepeatedly(Return(true));
+  // Prepare two frames for Draw() and DrawLastLayerTree().
+  EXPECT_CALL(*surface, AcquireFrame(SkISize()))
+      .WillOnce(Return(ByMove(std::move(surface_frame1))))
+      .WillOnce(Return(ByMove(std::move(surface_frame2))));
+  EXPECT_CALL(*surface, MakeRenderContextCurrent())
+      .WillOnce(Return(ByMove(std::make_unique<GLContextDefaultResult>(true))));
+  EXPECT_CALL(*external_view_embedder, SupportsDynamicThreadMerging)
+      .WillRepeatedly(Return(true));
+
+  EXPECT_CALL(*external_view_embedder,
+              BeginFrame(/*frame_size=*/SkISize(), /*context=*/nullptr,
+                         /*device_pixel_ratio=*/2.0,
+                         /*raster_thread_merger=*/_))
+      .Times(2);
+  EXPECT_CALL(*external_view_embedder, SubmitFrame).Times(2);
+  EXPECT_CALL(*external_view_embedder, EndFrame(/*should_resubmit_frame=*/false,
+                                                /*raster_thread_merger=*/_))
+      .Times(2);
+
+  rasterizer->Setup(std::move(surface));
+
+  auto pipeline = std::make_shared<Pipeline<LayerTree>>(/*depth=*/10);
+  auto layer_tree = std::make_unique<LayerTree>(/*frame_size=*/SkISize(),
+                                                /*device_pixel_ratio=*/2.0f);
+  bool result = pipeline->Produce().Complete(std::move(layer_tree));
+  EXPECT_TRUE(result);
+  auto no_discard = [](LayerTree&) { return false; };
+
+  // The Draw() will respectively call BeginFrame(), SubmitFrame() and
+  // EndFrame() one time.
+  rasterizer->Draw(CreateFinishedBuildRecorder(), pipeline, no_discard);
+
+  // The DrawLastLayerTree() will respectively call BeginFrame(), SubmitFrame()
+  // and EndFrame() one more time, totally 2 times.
+  rasterizer->DrawLastLayerTree(CreateFinishedBuildRecorder());
+}
+
 TEST(RasterizerTest, externalViewEmbedderDoesntEndFrameWhenNoSurfaceIsSet) {
   std::string test_name =
       ::testing::UnitTest::GetInstance()->current_test_info()->name();

engine/src/flutter/shell/platform/android/BUILD.gn

@@ -535,16 +535,6 @@ zip_bundle("flutter_jar_zip") {
   ]
 
   deps = [ ":android_jar" ]
-
-  if (current_cpu == "x86" || current_cpu == "x64") {
-    files += [
-      {
-        source = "$root_build_dir/lib.stripped/libflutter.so"
-        destination = "libflutter.so"
-      },
-    ]
-    deps += [ ":flutter_shell_native" ]
-  }
 }
 
 action("gen_android_javadoc") {