Optimize ParseRbsp method in H264 bitstream parser.

webrtc/common_video/h264/h264_common.h

 /*
  *  Copyright (c) 2016 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 58 matching lines @@
 // 00 00 01 -> 00 00 03 01
 // 00 00 02 -> 00 00 03 02
 // And things in the source that look like the emulation byte pattern (00 00 03)
 // need to have an extra emulation byte added, so it's removed when decoding:
 // 00 00 03 -> 00 00 03 03
 //
 // Decoding is simply a matter of finding any 00 00 03 sequence and removing
 // the 03 emulation byte.
 
 // Parse the given data and remove any emulation byte escaping.
-std::unique_ptr<rtc::Buffer> ParseRbsp(const uint8_t* data, size_t length);
+std::vector<uint8_t> ParseRbsp(const uint8_t* data, size_t length);
 
 // Write the given data to the destination buffer, inserting and emulation
 // bytes in order to escape any data the could be interpreted as a start
 // sequence.
 void WriteRbsp(const uint8_t* bytes, size_t length, rtc::Buffer* destination);
 }  // namespace H264
 }  // namespace webrtc
 
 #endif  // WEBRTC_COMMON_VIDEO_H264_H264_COMMON_H_