Parse FlexFEC RTP headers in Call and add integration with BWE.

webrtc/modules/congestion_controller/include/congestion_controller.h

Index: webrtc/modules/congestion_controller/include/congestion_controller.h
diff --git a/webrtc/modules/congestion_controller/include/congestion_controller.h b/webrtc/modules/congestion_controller/include/congestion_controller.h
index 004a84752eefe4f063d06850519074fef2d4dd1a..ba45e4f8357a535c3c9af293f926515d04456d5e 100644
--- a/webrtc/modules/congestion_controller/include/congestion_controller.h
+++ b/webrtc/modules/congestion_controller/include/congestion_controller.h
@@ -36,6 +36,7 @@ class RateLimiter;
 class RemoteBitrateEstimator;
 class RemoteBitrateObserver;
 class RtcEventLog;
+class RtpPacketReceived;
 class TransportFeedbackObserver;
 
 class CongestionController : public CallStatsObserver, public Module {
@@ -68,6 +69,8 @@ class CongestionController : public CallStatsObserver, public Module {
                        std::unique_ptr<PacedSender> pacer);
   virtual ~CongestionController();
 
+  virtual void NotifyBweOfReceivedPacket(const RtpPacketReceived& packet);
+
   virtual void SetBweBitrates(int min_bitrate_bps,
                               int start_bitrate_bps,
                               int max_bitrate_bps);