Reland "Update rtt on audio only calls".

webrtc/voice_engine/channel.h

Index: webrtc/voice_engine/channel.h
diff --git a/webrtc/voice_engine/channel.h b/webrtc/voice_engine/channel.h
index 8cac437f7b64462ce2f7764011f2fd56d5a6f10d..4056c7fb5688b5b7de5357ab70b876c2a1ef0c32 100644
--- a/webrtc/voice_engine/channel.h
+++ b/webrtc/voice_engine/channel.h
@@ -68,6 +68,7 @@ namespace voe {
 
 class OutputMixer;
 class RtcEventLogProxy;
+class RtcpRttStatsProxy;
 class RtpPacketSenderProxy;
 class Statistics;
 class StatisticsProxy;
@@ -413,6 +414,7 @@ class Channel
   // Set a RtcEventLog logging object.
   void SetRtcEventLog(RtcEventLog* event_log);
 
+  void SetRtcpRttStats(RtcpRttStats* rtcp_rtt_stats);
   void SetTransportOverhead(int transport_overhead_per_packet);
 
  protected:
@@ -450,6 +452,7 @@ class Channel
   ChannelState channel_state_;
 
   std::unique_ptr<voe::RtcEventLogProxy> event_log_proxy_;
+  std::unique_ptr<voe::RtcpRttStatsProxy> rtcp_rtt_stats_proxy_;
 
   std::unique_ptr<RtpHeaderParser> rtp_header_parser_;
   std::unique_ptr<RTPPayloadRegistry> rtp_payload_registry_;