Adjust RtcpReceiver to be testable with callbacks:

webrtc/modules/rtp_rtcp/source/rtp_rtcp_impl.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 205 matching lines @@
 }
 
 void ModuleRtpRtcpImpl::SetRtxSendPayloadType(int payload_type,
                                               int associated_payload_type) {
   rtp_sender_.SetRtxPayloadType(payload_type, associated_payload_type);
 }
 
 int32_t ModuleRtpRtcpImpl::IncomingRtcpPacket(
     const uint8_t* rtcp_packet,
     const size_t length) {
-  // Allow receive of non-compound RTCP packets.
-  RTCPUtility::RTCPParserV2 rtcp_parser(rtcp_packet, length, true);
-
-  const bool valid_rtcpheader = rtcp_parser.IsValid();
-  if (!valid_rtcpheader) {
-    LOG(LS_WARNING) << "Incoming invalid RTCP packet";
-    return -1;
-  }
-  RTCPHelp::RTCPPacketInformation rtcp_packet_information;
-  int32_t ret_val =
-      rtcp_receiver_.IncomingRTCPPacket(rtcp_packet_information, &rtcp_parser);
-  if (ret_val == 0) {
-    rtcp_receiver_.TriggerCallbacksFromRTCPPacket(rtcp_packet_information);
-  }
-  return ret_val;
+  return rtcp_receiver_.IncomingPacket(rtcp_packet, length) ? 0 : -1;
 }
 
 int32_t ModuleRtpRtcpImpl::RegisterSendPayload(
     const CodecInst& voice_codec) {
   return rtp_sender_.RegisterPayload(
       voice_codec.plname, voice_codec.pltype, voice_codec.plfreq,
       voice_codec.channels, (voice_codec.rate < 0) ? 0 : voice_codec.rate);
 }
 
 int32_t ModuleRtpRtcpImpl::RegisterSendPayload(const VideoCodec& video_codec) {
@@ skipping 705 matching lines @@
 void ModuleRtpRtcpImpl::RegisterSendChannelRtpStatisticsCallback(
     StreamDataCountersCallback* callback) {
   rtp_sender_.RegisterRtpStatisticsCallback(callback);
 }
 
 StreamDataCountersCallback*
     ModuleRtpRtcpImpl::GetSendChannelRtpStatisticsCallback() const {
   return rtp_sender_.GetRtpStatisticsCallback();
 }
 }  // namespace webrtc