Implement FrameMarking header extension support

webrtc/media/engine/webrtcvideoengine.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 505 matching lines @@
       webrtc::RtpExtension::kTransportSequenceNumberUri,
       webrtc::RtpExtension::kTransportSequenceNumberDefaultId));
   capabilities.header_extensions.push_back(
       webrtc::RtpExtension(webrtc::RtpExtension::kPlayoutDelayUri,
                            webrtc::RtpExtension::kPlayoutDelayDefaultId));
   if (IsVideoContentTypeExtensionFieldTrialEnabled()) {
     capabilities.header_extensions.push_back(
         webrtc::RtpExtension(webrtc::RtpExtension::kVideoContentTypeUri,
                              webrtc::RtpExtension::kVideoContentTypeDefaultId));
   }
+  capabilities.header_extensions.push_back(
+      webrtc::RtpExtension(webrtc::RtpExtension::kFrameMarkingUri,
+                           webrtc::RtpExtension::kFrameMarkingDefaultId));
   return capabilities;
 }
 
 void WebRtcVideoEngine::SetExternalDecoderFactory(
     WebRtcVideoDecoderFactory* decoder_factory) {
   RTC_DCHECK(!initialized_);
   external_decoder_factory_ = decoder_factory;
 }
 
 void WebRtcVideoEngine::SetExternalEncoderFactory(
@@ skipping 2133 matching lines @@
         rtx_mapping[video_codecs[i].codec.id] !=
             ulpfec_config.red_payload_type) {
       video_codecs[i].rtx_payload_type = rtx_mapping[video_codecs[i].codec.id];
     }
   }
 
   return video_codecs;
 }
 
 }  // namespace cricket