Inform jitter buffer about FlexFEC protection.

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 2268 matching lines @@
 
 void WebRtcVideoChannel2::WebRtcVideoReceiveStream::RecreateWebRtcStream() {
   if (flexfec_stream_) {
     call_->DestroyFlexfecReceiveStream(flexfec_stream_);
     flexfec_stream_ = nullptr;
   }
   if (stream_) {
     call_->DestroyVideoReceiveStream(stream_);
   }
   stream_ = call_->CreateVideoReceiveStream(config_.Copy());
-  stream_->Start();
   if (IsFlexfecFieldTrialEnabled() && flexfec_config_.IsCompleteAndEnabled()) {
     flexfec_stream_ = call_->CreateFlexfecReceiveStream(flexfec_config_);
     flexfec_stream_->Start();
   }
+  // Start VideoReceiveStream after FlexfecReceiveStream has been created,
+  // so that the former is aware of the existence of the latter.
+  stream_->Start();
 }
 
 void WebRtcVideoChannel2::WebRtcVideoReceiveStream::ClearDecoders(
     std::vector<AllocatedDecoder>* allocated_decoders) {
   for (size_t i = 0; i < allocated_decoders->size(); ++i) {
     if ((*allocated_decoders)[i].external) {
       external_decoder_factory_->DestroyVideoDecoder(
           (*allocated_decoders)[i].external_decoder);
     }
     delete (*allocated_decoders)[i].decoder;
@@ skipping 212 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