Reset the BWE when the network changes

webrtc/media/base/mediachannel.h

Index: webrtc/media/base/mediachannel.h
diff --git a/webrtc/media/base/mediachannel.h b/webrtc/media/base/mediachannel.h
index 68efbe798440edd0ce9214a8425b3c3e853545ea..fbc3538d9004c72bc122b76dece213018c01cff0 100644
--- a/webrtc/media/base/mediachannel.h
+++ b/webrtc/media/base/mediachannel.h
@@ -375,6 +375,8 @@ class MediaChannel : public sigslot::has_slots<> {
                               const rtc::PacketTime& packet_time) = 0;
   // Called when the socket's ability to send has changed.
   virtual void OnReadyToSend(bool ready) = 0;
+  // Called when the network used for sending packets changed.
+  virtual void OnNetworkChanged(int local_net_id, int remote_net_id) = 0;
   // Creates a new outgoing media stream with SSRCs and CNAME as described
   // by sp.
   virtual bool AddSendStream(const StreamParams& sp) = 0;
@@ -1098,6 +1100,8 @@ class DataMediaChannel : public MediaChannel {
   virtual bool SetSend(bool send) = 0;
   virtual bool SetReceive(bool receive) = 0;
 
+  virtual void OnNetworkChanged(int local_net_id, int remote_net_id) {}
+
   virtual bool SendData(
       const SendDataParams& params,
       const rtc::Buffer& payload,