Add content type information to encoded images and corresponding rtp extension header

webrtc/modules/rtp_rtcp/source/rtp_sender.cc

 /*
  *  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 175 matching lines @@
 int32_t RTPSender::RegisterRtpHeaderExtension(RTPExtensionType type,
                                               uint8_t id) {
   rtc::CritScope lock(&send_critsect_);
   switch (type) {
     case kRtpExtensionVideoRotation:
     case kRtpExtensionPlayoutDelay:
     case kRtpExtensionTransmissionTimeOffset:
     case kRtpExtensionAbsoluteSendTime:
     case kRtpExtensionAudioLevel:
     case kRtpExtensionTransportSequenceNumber:
+    case kRtpExtensionVideoContentType:
       return rtp_header_extension_map_.Register(type, id);
     case kRtpExtensionNone:
     case kRtpExtensionNumberOfExtensions:
       LOG(LS_ERROR) << "Invalid RTP extension type for registration.";
       return -1;
   }
   return -1;
 }
 
 bool RTPSender::IsRtpHeaderExtensionRegistered(RTPExtensionType type) const {
@@ skipping 1064 matching lines @@
     if (rtp_overhead_bytes_per_packet_ == packet.headers_size()) {
       return;
     }
     rtp_overhead_bytes_per_packet_ = packet.headers_size();
     overhead_bytes_per_packet = rtp_overhead_bytes_per_packet_;
   }
   overhead_observer_->OnOverheadChanged(overhead_bytes_per_packet);
 }
 
 }  // namespace webrtc