Introduce RtpStreamReceiver and RtpStreamReceiverControllerInterface.

webrtc/call/flexfec_receive_stream_impl.cc

Index: webrtc/call/flexfec_receive_stream_impl.cc
diff --git a/webrtc/call/flexfec_receive_stream_impl.cc b/webrtc/call/flexfec_receive_stream_impl.cc
index f01043349892574f5d240cacd27583173c68ad71..e45adf14cd800d2e3c37508697b5c18281d3a38a 100644
--- a/webrtc/call/flexfec_receive_stream_impl.cc
+++ b/webrtc/call/flexfec_receive_stream_impl.cc
@@ -15,6 +15,7 @@
 #include "webrtc/base/checks.h"
 #include "webrtc/base/location.h"
 #include "webrtc/base/logging.h"
+#include "webrtc/call/rtp_transport_controller_receive_interface.h"
 #include "webrtc/modules/rtp_rtcp/include/flexfec_receiver.h"
 #include "webrtc/modules/rtp_rtcp/include/receive_statistics.h"
 #include "webrtc/modules/rtp_rtcp/include/rtp_rtcp.h"
@@ -122,6 +123,7 @@ std::unique_ptr<RtpRtcp> CreateRtpRtcpModule(
 }  // namespace
 
 FlexfecReceiveStreamImpl::FlexfecReceiveStreamImpl(
+    RtpTransportControllerReceiveInterface* transport,
     const Config& config,
     RecoveredPacketReceiver* recovered_packet_receiver,
     RtcpRttStats* rtt_stats,
@@ -141,6 +143,11 @@ FlexfecReceiveStreamImpl::FlexfecReceiveStreamImpl(
   rtp_rtcp_->SetRTCPStatus(config_.rtcp_mode);
   rtp_rtcp_->SetSSRC(config_.local_ssrc);
   process_thread_->RegisterModule(rtp_rtcp_.get(), RTC_FROM_HERE);
+
+  // Register with transport.
+  // TODO(nisse): Register receiver_, and delete below OnRtpPacket method?
+  rtp_transport_receiver_ =
+      transport->CreateReceiver(config_.remote_ssrc, this);
 }
 
 FlexfecReceiveStreamImpl::~FlexfecReceiveStreamImpl() {