Cast: Add GetStats() extensions API.

chrome/renderer/media/cast_rtp_stream.h

 // Copyright 2013 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 CHROME_RENDERER_MEDIA_CAST_RTP_STREAM_H_
 #define CHROME_RENDERER_MEDIA_CAST_RTP_STREAM_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 107 matching lines @@
   void Stop();
 
   // Enables or disables logging for this stream.
   void ToggleLogging(bool enable);
 
   // Get serialized raw events for this stream and invokes |callback|
   // with the result.
   void GetRawEvents(
       const base::Callback<void(scoped_ptr<std::string>)>& callback);
 
+  // Get stats in JSON string and invokves |callback| with the result.
+  void GetStats(const base::Callback<void(scoped_ptr<std::string>)>& callback);
+
  private:
   // Return true if this track is an audio track. Return false if this
   // track is a video track.
   bool IsAudio() const;
 
   void DidEncounterError(const std::string& message);
 
   blink::WebMediaStreamTrack track_;
   const scoped_refptr<CastSession> cast_session_;
   scoped_ptr<CastAudioSink> audio_sink_;
   scoped_ptr<CastVideoSink> video_sink_;
   CastRtpParams params_;
   base::WeakPtrFactory<CastRtpStream> weak_factory_;
   base::Closure stop_callback_;
   ErrorCallback error_callback_;
 
   DISALLOW_COPY_AND_ASSIGN(CastRtpStream);
 };
 
 #endif  // CHROME_RENDERER_MEDIA_CAST_RTP_STREAM_H_