Reland of cc: Remove frame queuing from the scheduler.

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 35ba8e978350ef9d58009c65e2c87918b519082c..a2a6ac7f6e5b9a004b9997e1cd57a5761e25ad28 100644
--- a/cc/test/test_compositor_frame_sink.cc
+++ b/cc/test/test_compositor_frame_sink.cc
@@ -32,8 +32,7 @@ TestCompositorFrameSink::TestCompositorFrameSink(
                           std::move(worker_context_provider)),
       surface_manager_(new SurfaceManager),
       surface_id_allocator_(new SurfaceIdAllocator(kCompositorClientId)),
-      surface_factory_(new SurfaceFactory(surface_manager_.get(), this)),
-      weak_ptrs_(this) {
+      surface_factory_(new SurfaceFactory(surface_manager_.get(), this)) {
   std::unique_ptr<SyntheticBeginFrameSource> begin_frame_source;
   std::unique_ptr<DisplayScheduler> scheduler;
   if (!synchronous_composite) {
@@ -115,7 +114,6 @@ void TestCompositorFrameSink::DetachFromClient() {
   surface_factory_ = nullptr;
   surface_id_allocator_ = nullptr;
   surface_manager_ = nullptr;
-  weak_ptrs_.InvalidateWeakPtrs();
   CompositorFrameSink::DetachFromClient();
 }
 
@@ -139,7 +137,7 @@ void TestCompositorFrameSink::SwapBuffers(CompositorFrame frame) {
   surface_factory_->SubmitCompositorFrame(
       delegated_surface_id_, std::move(frame),
       base::Bind(&TestCompositorFrameSink::DidDrawCallback,
-                 weak_ptrs_.GetWeakPtr(), synchronous));
+                 base::Unretained(this)));
 
   for (std::unique_ptr<CopyOutputRequest>& copy_request : copy_requests_)
     surface_factory_->RequestCopyOfSurface(delegated_surface_id_,
@@ -150,17 +148,10 @@ void TestCompositorFrameSink::SwapBuffers(CompositorFrame frame) {
     display_->DrawAndSwap();
 }
 
-void TestCompositorFrameSink::DidDrawCallback(bool synchronous) {
+void TestCompositorFrameSink::DidDrawCallback() {
   // This is the frame ack to unthrottle the next frame, not actually a notice
   // that drawing is done.
-  if (synchronous) {
-    // For synchronous draws, this must be posted to a new stack because we are
-    // still the original call to SwapBuffers, and we want to leave that before
-    // saying that it is done.
-    CompositorFrameSink::PostSwapBuffersComplete();
-  } else {
-    client_->DidSwapBuffersComplete();
-  }
+  CompositorFrameSink::PostSwapBuffersComplete();
 }
 
 void TestCompositorFrameSink::ForceReclaimResources() {