Bug Fix: Rendering stuck due to thread issue of WebMediaPlayerMSCompositor

content/renderer/media/webmediaplayer_ms_compositor.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_RENDERER_MEDIA_WEBMEDIAPLAYER_MS_COMPOSITOR_H_
 #define CONTENT_RENDERER_MEDIA_WEBMEDIAPLAYER_MS_COMPOSITOR_H_
 
 #include <stddef.h>
 
 #include <map>
@@ skipping 60 matching lines @@
 
   // VideoFrameProvider implementation.
   void SetVideoFrameProviderClient(
       cc::VideoFrameProvider::Client* client) override;
   bool UpdateCurrentFrame(base::TimeTicks deadline_min,
                           base::TimeTicks deadline_max) override;
   bool HasCurrentFrame() override;
   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> current_frame();

[DaleCurtis, 2016/04/28 17:51:37]

hacker_style() methods must be inline. Please give this a different name like
GetCurrentFrameAndDontUpdateStatistics() or something similar.

[qiangchen, 2016/04/28 21:02:40]

Done.

+
   void StartRendering();
   void StopRendering();
   void ReplaceCurrentFrameWithACopy();
 
  private:
   friend class WebMediaPlayerMSTest;
 
   bool MapTimestampsToRenderTimeTicks(
       const std::vector<base::TimeDelta>& timestamps,
       std::vector<base::TimeTicks>* wall_clock_times);
@@ skipping 59 matching lines @@
   base::Lock current_frame_lock_;
 
   // Make sure the weak pointer factory member is the last member of the class.
   base::WeakPtrFactory<WebMediaPlayerMSCompositor> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(WebMediaPlayerMSCompositor);
 };
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_WEBMEDIAPLAYER_MS_COMPOSITOR_H_