Add content type extension to capabilities

webrtc/media/engine/webrtcvideoengine2.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 485 matching lines @@
                            webrtc::RtpExtension::kAbsSendTimeDefaultId));
   capabilities.header_extensions.push_back(
       webrtc::RtpExtension(webrtc::RtpExtension::kVideoRotationUri,
                            webrtc::RtpExtension::kVideoRotationDefaultId));
   capabilities.header_extensions.push_back(webrtc::RtpExtension(
       webrtc::RtpExtension::kTransportSequenceNumberUri,
       webrtc::RtpExtension::kTransportSequenceNumberDefaultId));
   capabilities.header_extensions.push_back(
       webrtc::RtpExtension(webrtc::RtpExtension::kPlayoutDelayUri,
                            webrtc::RtpExtension::kPlayoutDelayDefaultId));
+  capabilities.header_extensions.push_back(

[brandtr, 2017/04/12 16:22:10]

Will this addition launch the header extension in the default SDP?

+        webrtc::RtpExtension(webrtc::RtpExtension::kVideoContentTypeUri,
+                             webrtc::RtpExtension::kVideoContentTypeDefaultId));
   return capabilities;
 }
 
 void WebRtcVideoEngine2::SetExternalDecoderFactory(
     WebRtcVideoDecoderFactory* decoder_factory) {
   RTC_DCHECK(!initialized_);
   external_decoder_factory_ = decoder_factory;
 }
 
 void WebRtcVideoEngine2::SetExternalEncoderFactory(
@@ skipping 2045 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