Wire-up audio BWE with overhead.

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 4056c7fb5688b5b7de5357ab70b876c2a1ef0c32..01907d269b1fa2eab5ce5396a1e09f16ce3e326b 100644
--- a/webrtc/voice_engine/channel.h
+++ b/webrtc/voice_engine/channel.h
@@ -144,8 +144,8 @@ class Channel
       public AudioPacketizationCallback,  // receive encoded packets from the
                                           // ACM
       public ACMVADCallback,              // receive voice activity from the ACM
-      public MixerParticipant  // supplies output mixer with audio frames
-{
+      public MixerParticipant,  // supplies output mixer with audio frames
+      public OverheadObserver {
  public:
   friend class VoERtcpObserver;
 
@@ -417,6 +417,9 @@ class Channel
   void SetRtcpRttStats(RtcpRttStats* rtcp_rtt_stats);
   void SetTransportOverhead(int transport_overhead_per_packet);
 
+  // From OverheadObserver in the RTP/RTCP module

[stefan-webrtc, 2016/12/14 11:44:20]

End with "."

+  void OnOverheadChanged(size_t overhead_bytes_per_packet) override;
+
  protected:
   void OnIncomingFractionLoss(int fraction_lost);