Reland of Move MutableDataY{,U,V} methods to I420Buffer only.

webrtc/modules/video_capture/video_capture_impl.h

 /*
  *  Copyright (c) 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 119 matching lines @@
     int32_t _setCaptureDelay; // The currently used capture delay
     VideoCaptureDataCallback* _dataCallBack;
     VideoCaptureFeedBack* _captureCallBack;
 
     int64_t _lastProcessFrameTimeNanos;
     // timestamp for local captured frames
     int64_t _incomingFrameTimesNanos[kFrameRateCountHistorySize];
     VideoRotation _rotateFrame;  // Set if the frame should be rotated by the
                                  // capture module.
 
-    VideoFrame _captureFrame;
-
     // Indicate whether rotation should be applied before delivered externally.
     bool apply_rotation_;
 };
 }  // namespace videocapturemodule
 }  // namespace webrtc
 #endif  // WEBRTC_MODULES_VIDEO_CAPTURE_MAIN_SOURCE_VIDEO_CAPTURE_IMPL_H_