Bug Fix: Data Race For WebMediaPlayerMS' Frame Count Variable

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 46 matching lines @@
   WebMediaPlayerMSCompositor(
       const scoped_refptr<base::SingleThreadTaskRunner>& compositor_task_runner,
       const blink::WebMediaStream& web_stream,
       const base::WeakPtr<WebMediaPlayerMS>& player);
 
   void EnqueueFrame(scoped_refptr<media::VideoFrame> frame);
 
   // Statistical data
   gfx::Size GetCurrentSize();
   base::TimeDelta GetCurrentTime();
-  size_t total_frame_count() const;
-  size_t dropped_frame_count() const;
+  size_t total_frame_count();
+  size_t dropped_frame_count();
 
   // 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;
 
@@ skipping 82 matching lines @@
 
   // |current_frame_lock_| protects |current_frame_used_by_compositor_|,
   // |current_frame_|, and |rendering_frame_buffer_|.
   base::Lock current_frame_lock_;
 
   DISALLOW_COPY_AND_ASSIGN(WebMediaPlayerMSCompositor);
 };
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_WEBMEDIAPLAYER_MS_COMPOSITOR_H_