Wire up rtcp xr target bitrate on receive side.

webrtc/modules/rtp_rtcp/include/rtp_rtcp.h

 /*
  *  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 16 matching lines @@
 namespace webrtc {
 
 // Forward declarations.
 class OverheadObserver;
 class RateLimiter;
 class ReceiveStatistics;
 class RemoteBitrateEstimator;
 class RtcEventLog;
 class RtpReceiver;
 class Transport;
+class VideoBitrateAllocationObserver;
 
 RTPExtensionType StringToRtpExtensionType(const std::string& extension);
 
 namespace rtcp {
 class TransportFeedback;
 }
 
 class RtpRtcp : public Module {
  public:
   struct Configuration {
@@ skipping 14 matching lines @@
     Transport* outgoing_transport = nullptr;
 
     // Called when the receiver request a intra frame.
     RtcpIntraFrameObserver* intra_frame_callback = nullptr;
 
     // Called when we receive a changed estimate from the receiver of out
     // stream.
     RtcpBandwidthObserver* bandwidth_callback = nullptr;
 
     TransportFeedbackObserver* transport_feedback_callback = nullptr;
+    VideoBitrateAllocationObserver* bitrate_allocation_observer = nullptr;
     RtcpRttStats* rtt_stats = nullptr;
     RtcpPacketTypeCounterObserver* rtcp_packet_type_counter_observer = nullptr;
 
     // Estimates the bandwidth available for a set of streams from the same
     // client.
     RemoteBitrateEstimator* remote_bitrate_estimator = nullptr;
 
     // Spread any bursts of packets into smaller bursts to minimize packet loss.
     RtpPacketSender* paced_sender = nullptr;
 
@@ skipping 398 matching lines @@
   virtual int32_t SetKeyFrameRequestMethod(KeyFrameRequestMethod method) = 0;
 
   // Sends a request for a keyframe.
   // Returns -1 on failure else 0.
   virtual int32_t RequestKeyFrame() = 0;
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_RTP_RTCP_INCLUDE_RTP_RTCP_H_