Bug Fix: Rendering stuck due to thread issue of WebMediaPlayerMSCompositor (M51)

content/renderer/media/webmediaplayer_ms_compositor.h

Index: content/renderer/media/webmediaplayer_ms_compositor.h
diff --git a/content/renderer/media/webmediaplayer_ms_compositor.h b/content/renderer/media/webmediaplayer_ms_compositor.h
index 5c2c4d1975b098e47a1638a43178500598832967..81a9b16b071b0f9a64bea311492fe9987ab82c8f 100644
--- a/content/renderer/media/webmediaplayer_ms_compositor.h
+++ b/content/renderer/media/webmediaplayer_ms_compositor.h
@@ -78,6 +78,13 @@ class CONTENT_EXPORT WebMediaPlayerMSCompositor
   scoped_refptr<media::VideoFrame> GetCurrentFrame() override;
   void PutCurrentFrame() override;
 
+  // Return the current frame being rendered.
+  // Difference between GetCurrentFrame(): GetCurrentFrame() is designed for
+  // chrome compositor to pull frame from WebMediaPlayerMSCompositor, and thus
+  // calling GetCurrentFrame() will affect statistics like |dropped_frames_|
+  // etc. Calling this function has no side effect.
+  scoped_refptr<media::VideoFrame> GetCurrentFrameWithoutUpdatingStatistics();
+
   void StartRendering();
   void StopRendering();
   void ReplaceCurrentFrameWithACopy();