cc: Get rid of PostSwapBuffersComplete.

cc/test/test_compositor_frame_sink.cc

Index: cc/test/test_compositor_frame_sink.cc
diff --git a/cc/test/test_compositor_frame_sink.cc b/cc/test/test_compositor_frame_sink.cc
index 2800db713edb14d0b66fefa06edda68488133901..0974cde40fde2bbbcc626caaba7f4b6c6ec9a795 100644
--- a/cc/test/test_compositor_frame_sink.cc
+++ b/cc/test/test_compositor_frame_sink.cc
@@ -25,40 +25,42 @@ TestCompositorFrameSink::TestCompositorFrameSink(
     SharedBitmapManager* shared_bitmap_manager,
     gpu::GpuMemoryBufferManager* gpu_memory_buffer_manager,
     const RendererSettings& renderer_settings,
-    base::SingleThreadTaskRunner* task_runner,
+    scoped_refptr<base::SingleThreadTaskRunner> task_runner,
     bool synchronous_composite,
     bool force_disable_reclaim_resources)
     : CompositorFrameSink(std::move(compositor_context_provider),
                           std::move(worker_context_provider)),
+      task_runner_(std::move(task_runner)),
       frame_sink_id_(kCompositorFrameSinkId),
       surface_manager_(new SurfaceManager),
       surface_id_allocator_(new SurfaceIdAllocator()),
       surface_factory_(
           new SurfaceFactory(frame_sink_id_, surface_manager_.get(), this)),
       display_context_shared_with_compositor_(
-          display_output_surface->context_provider() == context_provider()) {
+          display_output_surface->context_provider() == context_provider()),
+      weak_ptr_factory_(this) {
   std::unique_ptr<SyntheticBeginFrameSource> begin_frame_source;
   std::unique_ptr<DisplayScheduler> scheduler;
   if (!synchronous_composite) {
     if (renderer_settings.disable_display_vsync) {
       begin_frame_source.reset(new BackToBackBeginFrameSource(
-          base::MakeUnique<DelayBasedTimeSource>(task_runner)));
+          base::MakeUnique<DelayBasedTimeSource>(task_runner_.get())));
     } else {
       begin_frame_source.reset(new DelayBasedBeginFrameSource(
-          base::MakeUnique<DelayBasedTimeSource>(task_runner)));
+          base::MakeUnique<DelayBasedTimeSource>(task_runner_.get())));
       begin_frame_source->SetAuthoritativeVSyncInterval(
           base::TimeDelta::FromMilliseconds(1000.f /
                                             renderer_settings.refresh_rate));
     }
     scheduler.reset(new DisplayScheduler(
-        begin_frame_source.get(), task_runner,
+        begin_frame_source.get(), task_runner_.get(),
         display_output_surface->capabilities().max_frames_pending));
   }
   display_.reset(
       new Display(shared_bitmap_manager, gpu_memory_buffer_manager,
                   renderer_settings, std::move(begin_frame_source),
                   std::move(display_output_surface), std::move(scheduler),
-                  base::MakeUnique<TextureMailboxDeleter>(task_runner)));
+                  base::MakeUnique<TextureMailboxDeleter>(task_runner_.get())));
 
   // Since this CompositorFrameSink and the Display are tightly coupled and in
   // the same process/thread, the LayerTreeHostImpl can reclaim resources from
@@ -132,10 +134,18 @@ void TestCompositorFrameSink::SwapBuffers(CompositorFrame frame) {
 
   bool synchronous = !display_->has_scheduler();
 
-  surface_factory_->SubmitCompositorFrame(
-      delegated_local_frame_id_, std::move(frame),
-      base::Bind(&TestCompositorFrameSink::DidDrawCallback,
-                 base::Unretained(this)));
+  SurfaceFactory::DrawCallback draw_callback;
+  if (!synchronous) {
+    // For async draws, we use a callback tell when it is done, but for sync
+    // draws we don't need one. Unretained is safe here because the callback
+    // will be run when |surface_factory_| is destroyed which is owned by this
+    // class.
+    draw_callback = base::Bind(&TestCompositorFrameSink::DidDrawCallback,
+                               base::Unretained(this));
+  }
+
+  surface_factory_->SubmitCompositorFrame(delegated_local_frame_id_,
+                                          std::move(frame), draw_callback);
 
   for (std::unique_ptr<CopyOutputRequest>& copy_request : copy_requests_) {
     surface_factory_->RequestCopyOfSurface(delegated_local_frame_id_,
@@ -143,14 +153,20 @@ void TestCompositorFrameSink::SwapBuffers(CompositorFrame frame) {
   }
   copy_requests_.clear();
 
-  if (synchronous)
+  if (synchronous) {
     display_->DrawAndSwap();
+    // Post this to get a new stack frame so that we exit this function before
+    // calling the client to tell it that it is done.
+    task_runner_->PostTask(FROM_HERE,
+                           base::Bind(&TestCompositorFrameSink::DidDrawCallback,
+                                      weak_ptr_factory_.GetWeakPtr()));
+  }
 }
 
 void TestCompositorFrameSink::DidDrawCallback() {
   // This is the frame ack to unthrottle the next frame, not actually a notice
   // that drawing is done.
-  CompositorFrameSink::PostSwapBuffersComplete();
+  client_->DidSwapBuffersComplete();
 }
 
 void TestCompositorFrameSink::ForceReclaimResources() {