Get VideoCapturer stats via VideoTrackSourceInterface in StatsCollector,

webrtc/media/engine/webrtcvideoengine2.cc

 /*
  *  Copyright (c) 2014 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 2071 matching lines @@
     if (stream_ == NULL)
       return info;
 
     stats = stream_->GetStats();
   }
   info.adapt_changes = number_of_cpu_adapt_changes_;
   info.adapt_reason = cpu_restricted_counter_ <= 0
                           ? CoordinatedVideoAdapter::ADAPTREASON_NONE
                           : CoordinatedVideoAdapter::ADAPTREASON_CPU;
 
-  if (capturer_) {
-      VideoFormat last_captured_frame_format;
-      capturer_->GetStats(&last_captured_frame_format);
-      info.input_frame_width = last_captured_frame_format.width;
-      info.input_frame_height = last_captured_frame_format.height;
-  }
-
   // Get bandwidth limitation info from stream_->GetStats().
   // Input resolution (output from video_adapter) can be further scaled down or
   // higher video layer(s) can be dropped due to bitrate constraints.
   // Note, adapt_changes only include changes from the video_adapter.
   if (stats.bw_limited_resolution)
     info.adapt_reason |= CoordinatedVideoAdapter::ADAPTREASON_BANDWIDTH;
 
   info.encoder_implementation_name = stats.encoder_implementation_name;
   info.ssrc_groups = ssrc_groups_;
   info.framerate_input = stats.input_frame_rate;
@@ skipping 484 matching lines @@
         rtx_mapping[video_codecs[i].codec.id] !=
             fec_settings.red_payload_type) {
       video_codecs[i].rtx_payload_type = rtx_mapping[video_codecs[i].codec.id];
     }
   }
 
   return video_codecs;
 }
 
 }  // namespace cricket