Add RemoteEstimatorProxy for capturing receive times

webrtc/modules/rtp_rtcp/source/rtcp_packet/transport_feedback.cc

Index: webrtc/modules/rtp_rtcp/source/rtcp_packet/transport_feedback.cc
diff --git a/webrtc/modules/rtp_rtcp/source/rtcp_packet/transport_feedback.cc b/webrtc/modules/rtp_rtcp/source/rtcp_packet/transport_feedback.cc
index b426887d06ee8c7dc2bd54ba2119f5f458a87133..54651d9ce5441f113c31e4a052a7dd7a23dc2f9f 100644
--- a/webrtc/modules/rtp_rtcp/source/rtcp_packet/transport_feedback.cc
+++ b/webrtc/modules/rtp_rtcp/source/rtcp_packet/transport_feedback.cc
@@ -304,6 +304,13 @@ void TransportFeedback::WithMediaSourceSsrc(uint32_t ssrc) {
   media_source_ssrc_ = ssrc;
 }
 
+uint32_t TransportFeedback::GetPacketSenderSsrc() const {
+  return packet_sender_ssrc_;
+}
+
+uint32_t TransportFeedback::GetMediaSourceSsrc() const {
+  return media_source_ssrc_;
+}
 void TransportFeedback::WithBase(uint16_t base_sequence,
                                  int64_t ref_timestamp_us) {
   DCHECK_EQ(-1, base_seq_);
@@ -531,7 +538,7 @@ int32_t TransportFeedback::GetBaseTime() const {
 }
 
 int64_t TransportFeedback::GetBaseTimeUs() const {
-  return GetBaseTime() * kBaseScaleFactor;
+  return base_time_ * kBaseScaleFactor;
 }
 
 std::vector<TransportFeedback::StatusSymbol>