Move passing of WebRTC rendering frames from main thread to compositor thread

content/renderer/media/webmediaplayer_ms_compositor.cc

Index: content/renderer/media/webmediaplayer_ms_compositor.cc
diff --git a/content/renderer/media/webmediaplayer_ms_compositor.cc b/content/renderer/media/webmediaplayer_ms_compositor.cc
index 86e1a896411438311abd59784c47512d62d121c0..5067c9346989d8c0580b1b13306b8273d982164a 100644
--- a/content/renderer/media/webmediaplayer_ms_compositor.cc
+++ b/content/renderer/media/webmediaplayer_ms_compositor.cc
@@ -135,7 +135,7 @@ WebMediaPlayerMSCompositor::WebMediaPlayerMSCompositor(
       total_frame_count_(0),
       dropped_frame_count_(0),
       stopped_(true),
-      weak_ptr_factory_(this) {
+      weak_factory_for_compositor_(this) {
   main_message_loop_ = base::MessageLoop::current();
 
   blink::WebVector<blink::WebMediaStreamTrack> video_tracks;
@@ -204,7 +204,7 @@ void WebMediaPlayerMSCompositor::SetVideoFrameProviderClient(
 
 void WebMediaPlayerMSCompositor::EnqueueFrame(
     const scoped_refptr<media::VideoFrame>& frame) {
-  DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK(compositor_task_runner_->BelongsToCurrentThread());
   base::AutoLock auto_lock(current_frame_lock_);
   ++total_frame_count_;
 
@@ -318,7 +318,7 @@ void WebMediaPlayerMSCompositor::StartRendering() {
   DCHECK(thread_checker_.CalledOnValidThread());
   compositor_task_runner_->PostTask(
       FROM_HERE, base::Bind(&WebMediaPlayerMSCompositor::StartRenderingInternal,
-                            weak_ptr_factory_.GetWeakPtr()));
+                            GetWeakPtr()));
 }
 
 void WebMediaPlayerMSCompositor::StartRenderingInternal() {
@@ -333,7 +333,7 @@ void WebMediaPlayerMSCompositor::StopRendering() {
   DCHECK(thread_checker_.CalledOnValidThread());
   compositor_task_runner_->PostTask(
       FROM_HERE, base::Bind(&WebMediaPlayerMSCompositor::StopRenderingInternal,
-                            weak_ptr_factory_.GetWeakPtr()));
+                            GetWeakPtr()));
 }
 
 void WebMediaPlayerMSCompositor::StopRenderingInternal() {
@@ -368,6 +368,11 @@ void WebMediaPlayerMSCompositor::ReplaceCurrentFrameWithACopy() {
       CopyFrame(current_frame_, player_->GetSkCanvasVideoRenderer());
 }
 
+base::WeakPtr<WebMediaPlayerMSCompositor>
+WebMediaPlayerMSCompositor::GetWeakPtr() {
+  return weak_factory_for_compositor_.GetWeakPtr();
+}
+
 bool WebMediaPlayerMSCompositor::MapTimestampsToRenderTimeTicks(
     const std::vector<base::TimeDelta>& timestamps,
     std::vector<base::TimeTicks>* wall_clock_times) {