Fixing flakiness of TextureLayerChangeInvisibleMailboxTest

cc/trees/single_thread_proxy.cc

Index: cc/trees/single_thread_proxy.cc
diff --git a/cc/trees/single_thread_proxy.cc b/cc/trees/single_thread_proxy.cc
index 0386145c7c55fea08e4f34362dd5f3536b1b1a02..668ba9190cd9503a5ddbd131ca574c17f3ed57a0 100644
--- a/cc/trees/single_thread_proxy.cc
+++ b/cc/trees/single_thread_proxy.cc
@@ -52,6 +52,7 @@ SingleThreadProxy::SingleThreadProxy(LayerTreeHost* layer_tree_host,
       inside_synchronous_composite_(false),
       compositor_frame_sink_creation_requested_(false),
       compositor_frame_sink_lost_(true),
+      compositor_frame_sink_weak_factory_(this),
       weak_factory_(this) {
   TRACE_EVENT0("cc", "SingleThreadProxy::SingleThreadProxy");
   DCHECK(task_runner_provider_);
@@ -123,6 +124,7 @@ void SingleThreadProxy::RequestNewCompositorFrameSink() {
 
 void SingleThreadProxy::ReleaseCompositorFrameSink() {
   compositor_frame_sink_lost_ = true;
+  compositor_frame_sink_weak_factory_.InvalidateWeakPtrs();
   if (scheduler_on_impl_thread_)
     scheduler_on_impl_thread_->DidLoseCompositorFrameSink();
   return layer_tree_host_impl_->ReleaseCompositorFrameSink();
@@ -403,6 +405,7 @@ void SingleThreadProxy::DidCompletePageScaleAnimationOnImplThread() {
 void SingleThreadProxy::DidLoseCompositorFrameSinkOnImplThread() {
   TRACE_EVENT0("cc",
                "SingleThreadProxy::DidLoseCompositorFrameSinkOnImplThread");
+  compositor_frame_sink_weak_factory_.InvalidateWeakPtrs();
   {
     DebugScopedSetMainThread main(task_runner_provider_);
     // This must happen before we notify the scheduler as it may try to recreate
@@ -425,7 +428,12 @@ void SingleThreadProxy::DidReceiveCompositorFrameAckOnImplThread() {
                "SingleThreadProxy::DidReceiveCompositorFrameAckOnImplThread");
   if (scheduler_on_impl_thread_)
     scheduler_on_impl_thread_->DidReceiveCompositorFrameAck();
-  layer_tree_host_->DidReceiveCompositorFrameAck();
+  // We do a PostTask here because freeing resources in some cases (such as in
+  // TextureLayer) is PostTasked and we want to make sure ack is received after
+  // resources are returned.
+  task_runner_provider_->MainThreadTaskRunner()->PostTask(
+      FROM_HERE, base::Bind(&SingleThreadProxy::DidReceiveCompositorFrameAck,
+                            compositor_frame_sink_weak_factory_.GetWeakPtr()));
 }
 
 void SingleThreadProxy::OnDrawForCompositorFrameSink(
@@ -794,4 +802,8 @@ void SingleThreadProxy::DidFinishImplFrame() {
 #endif
 }
 
+void SingleThreadProxy::DidReceiveCompositorFrameAck() {
+  layer_tree_host_->DidReceiveCompositorFrameAck();
+}
+
 }  // namespace cc