Implement timing frames.

webrtc/test/constants.cc

 /*
  *  Copyright (c) 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.
  */
 
 #include "webrtc/test/constants.h"
 
 namespace webrtc {
 namespace test {
 
 const int kTOffsetExtensionId = 6;
 const int kAbsSendTimeExtensionId = 7;
 const int kTransportSequenceNumberExtensionId = 8;
 const int kVideoRotationExtensionId = 9;
 const int kVideoContentTypeExtensionId = 10;
+const int kVideoTimingExtensionId = 11;
 
 }  // namespace test
 }  // namespace webrtc