Piggybacking simulcast id and ALR experiment id into video content type extension.

webrtc/modules/video_coding/encoded_frame.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 69 matching lines @@
   _payloadType = 0;
   _frameType = kVideoFrameDelta;
   _encodedWidth = 0;
   _encodedHeight = 0;
   _completeFrame = false;
   _missingFrame = false;
   _length = 0;
   _codecSpecificInfo.codecType = kVideoCodecUnknown;
   _codec = kVideoCodecUnknown;
   rotation_ = kVideoRotation_0;
-  content_type_ = VideoContentType::UNSPECIFIED;
+  content_type_ = VideoContentType::Unspecified();
   timing_.flags = TimingFrameFlags::kInvalid;
   _rotation_set = false;
 }
 
 void VCMEncodedFrame::CopyCodecSpecific(const RTPVideoHeader* header) {
   if (header) {
     switch (header->codec) {
       case kRtpVideoVp8: {
         if (_codecSpecificInfo.codecType != kVideoCodecVP8) {
           // This is the first packet for this frame.
@@ skipping 108 matching lines @@
       // copy old data
       memcpy(newBuffer, _buffer, _size);
       delete[] _buffer;
     }
     _buffer = newBuffer;
     _size = minimumSize;
   }
 }
 
 }  // namespace webrtc