Android: Make VideoCapturer an interface for all VideoCapturers to implement

webrtc/api/androidvideocapturer.cc

 /*
  *  Copyright 2015 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 208 matching lines @@
   RTC_CHECK(thread_checker_.CalledOnValidThread());
   const cricket::VideoFormat& current = video_adapter()->output_format();
   cricket::VideoFormat format(
       width, height, cricket::VideoFormat::FpsToInterval(fps), current.fourcc);
   video_adapter()->OnOutputFormatRequest(format);
 }
 
 bool AndroidVideoCapturer::GetBestCaptureFormat(
     const cricket::VideoFormat& desired,
     cricket::VideoFormat* best_format) {
-  // Delegate this choice to VideoCapturerAndroid.startCapture().
+  // Delegate this choice to VideoCapturer.startCapture().
   *best_format = desired;
   return true;
 }
 
 }  // namespace webrtc