Add QP sum stats for received streams.

webrtc/video/video_receive_stream.cc

Index: webrtc/video/video_receive_stream.cc
diff --git a/webrtc/video/video_receive_stream.cc b/webrtc/video/video_receive_stream.cc
index 183f72b537fcf9e6f75afb6bfebe44eaf648275a..21bb42872f3a9ef3c6ede8006e611b314cec5775 100644
--- a/webrtc/video/video_receive_stream.cc
+++ b/webrtc/video/video_receive_stream.cc
@@ -381,10 +381,6 @@ VideoReceiveStream::Stats VideoReceiveStream::GetStats() const {
 
 // TODO(tommi): This method grabs a lock 6 times.
 void VideoReceiveStream::OnFrame(const VideoFrame& video_frame) {
-  // TODO(tommi): OnDecodedFrame grabs a lock, incidentally the same lock
-  // that OnSyncOffsetUpdated() and OnRenderedFrame() below grab.
-  stats_proxy_.OnDecodedFrame();
-
   int64_t sync_offset_ms;
   double estimated_freq_khz;
   // TODO(tommi): GetStreamSyncOffsetInMs grabs three locks.  One inside the