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

webrtc/modules/video_coding/codecs/h264/h264_encoder_impl.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.
  *
  */
@@ skipping 349 matching lines @@
     ReportError();
     return WEBRTC_VIDEO_CODEC_ERROR;
   }
 
   encoded_image_._encodedWidth = frame_buffer->width();
   encoded_image_._encodedHeight = frame_buffer->height();
   encoded_image_._timeStamp = input_frame.timestamp();
   encoded_image_.ntp_time_ms_ = input_frame.ntp_time_ms();
   encoded_image_.capture_time_ms_ = input_frame.render_time_ms();
   encoded_image_.rotation_ = input_frame.rotation();
+  encoded_image_.content_type_ = (mode_ == kScreensharing)
+                                     ? VideoContentType::SCREENSHARE
+                                     : VideoContentType::UNSPECIFIED;
   encoded_image_._frameType = ConvertToVideoFrameType(info.eFrameType);
 
   // Split encoded image up into fragments. This also updates |encoded_image_|.
   RTPFragmentationHeader frag_header;
   RtpFragmentize(&encoded_image_, &encoded_image_buffer_, *frame_buffer, &info,
                  &frag_header);
 
   // Encoder can skip frames to save bandwidth in which case
   // |encoded_image_._length| == 0.
   if (encoded_image_._length > 0) {
@@ skipping 114 matching lines @@
 
 int32_t H264EncoderImpl::SetPeriodicKeyFrames(bool enable) {
   return WEBRTC_VIDEO_CODEC_OK;
 }
 
 VideoEncoder::ScalingSettings H264EncoderImpl::GetScalingSettings() const {
   return VideoEncoder::ScalingSettings(true);
 }
 
 }  // namespace webrtc