Add TransportFeedback adapter, adapting remote feedback to bwe estiamtor

webrtc/modules/rtp_rtcp/interface/rtp_rtcp.h

Index: webrtc/modules/rtp_rtcp/interface/rtp_rtcp.h
diff --git a/webrtc/modules/rtp_rtcp/interface/rtp_rtcp.h b/webrtc/modules/rtp_rtcp/interface/rtp_rtcp.h
index 6aa4687f8eb842157133bc4f13a370771b5ae634..15e0ffce8e277724d98935b728d5a7d9f4691e3f 100644
--- a/webrtc/modules/rtp_rtcp/interface/rtp_rtcp.h
+++ b/webrtc/modules/rtp_rtcp/interface/rtp_rtcp.h
@@ -65,7 +65,7 @@ class RtpRtcp : public Module {
     Transport* outgoing_transport;
     RtcpIntraFrameObserver* intra_frame_callback;
     RtcpBandwidthObserver* bandwidth_callback;
-    SendTimeObserver* send_time_callback;
+    TransportFeedbackObserver* transport_feedback_callback;
     RtcpRttStats* rtt_stats;
     RtcpPacketTypeCounterObserver* rtcp_packet_type_counter_observer;
     RtpAudioFeedback* audio_messages;