Revert of Change VideoCaptureDeliverFrameCB's signature

content/renderer/media/video_track_adapter.h

 // Copyright 2014 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_VIDEO_TRACK_ADAPTER_H_
 #define CONTENT_RENDERER_MEDIA_VIDEO_TRACK_ADAPTER_H_
 
 #include <vector>
 
 #include "base/macros.h"
@@ skipping 30 matching lines @@
   void AddTrack(const MediaStreamVideoTrack* track,
                 VideoCaptureDeliverFrameCB frame_callback,
                 int max_width, int max_height,
                 double min_aspect_ratio,
                 double max_aspect_ratio,
                 double max_frame_rate);
   void RemoveTrack(const MediaStreamVideoTrack* track);
 
   // Delivers |frame| to all tracks that have registered a callback.
   // Must be called on the IO-thread.
-  void DeliverFrameOnIO(const scoped_refptr<media::VideoFrame>& frame,
-                        base::TimeTicks estimated_capture_time);
+  void DeliverFrameOnIO(
+      const scoped_refptr<media::VideoFrame>& frame,
+      const base::TimeTicks& estimated_capture_time);
 
   base::SingleThreadTaskRunner* io_task_runner() const {
     DCHECK(thread_checker_.CalledOnValidThread());
     return io_task_runner_.get();
   }
 
   // Start monitor that frames are delivered to this object. I.E, that
   // |DeliverFrameOnIO| is called with a frame rate of |source_frame_rate|.
   // |on_muted_callback| is triggered on the main render thread.
   void StartFrameMonitoring(double source_frame_rate,
@@ skipping 53 matching lines @@
 
   // Frame rate configured on the video source, accessed on the IO-thread.
   float source_frame_rate_;
 
   DISALLOW_COPY_AND_ASSIGN(VideoTrackAdapter);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_VIDEO_TRACK_ADAPTER_H_