Reland "Update rtt on audio only calls".

webrtc/voice_engine/channel_proxy.cc

Index: webrtc/voice_engine/channel_proxy.cc
diff --git a/webrtc/voice_engine/channel_proxy.cc b/webrtc/voice_engine/channel_proxy.cc
index 04fa93f6ab74403049301fc1726f6d962c3ce12f..2dd74facb4f550d5ea357ec6ab081d26b20770c8 100644
--- a/webrtc/voice_engine/channel_proxy.cc
+++ b/webrtc/voice_engine/channel_proxy.cc
@@ -249,6 +249,11 @@ void ChannelProxy::DisassociateSendChannel() {
   channel()->set_associate_send_channel(ChannelOwner(nullptr));
 }
 
+void ChannelProxy::SetRtcpRttStats(RtcpRttStats* rtcp_rtt_stats) {
+  RTC_DCHECK(thread_checker_.CalledOnValidThread());
+  channel()->SetRtcpRttStats(rtcp_rtt_stats);
+}
+
 Channel* ChannelProxy::channel() const {
   RTC_DCHECK(channel_owner_.channel());
   return channel_owner_.channel();