Get VideoCapturer stats via VideoTrackSourceInterface in StatsCollector,

webrtc/api/statscollector.h

 /*
  *  Copyright 2012 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 95 matching lines @@
 
   StatsReport* AddConnectionInfoReport(const std::string& content_name,
       int component, int connection_id,
       const StatsReport::Id& channel_report_id,
       const cricket::ConnectionInfo& info);
 
   void ExtractDataInfo();
   void ExtractSessionInfo();
   void ExtractVoiceInfo();
   void ExtractVideoInfo(PeerConnectionInterface::StatsOutputLevel level);
+  void ExtractSenderInfo();
   void BuildSsrcToTransportId();
   webrtc::StatsReport* GetReport(const StatsReport::StatsType& type,
                                  const std::string& id,
                                  StatsReport::Direction direction);
 
   // Helper method to get stats from the local audio tracks.
   void UpdateStatsFromExistingLocalAudioTracks();
   void UpdateReportFromAudioTrack(AudioTrackInterface* track,
                                   StatsReport* report);
 
@@ skipping 17 matching lines @@
   // TODO(tommi): We appear to be holding on to raw pointers to reference
   // counted objects?  We should be using scoped_refptr here.
   typedef std::vector<std::pair<AudioTrackInterface*, uint32_t> >
       LocalAudioTrackVector;
   LocalAudioTrackVector local_audio_tracks_;
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_API_STATSCOLLECTOR_H_