Introduce rtc::PacketTransportInterface and let cricket::TransportChannel inherit.

webrtc/p2p/base/transportcontroller.h

Index: webrtc/p2p/base/transportcontroller.h
diff --git a/webrtc/p2p/base/transportcontroller.h b/webrtc/p2p/base/transportcontroller.h
index 5f3fccc868822a1eda564345d7e2a5c7ce7b0d2e..83920f62c3d4d6fe4e864daeb25bf5037aaa6c73 100644
--- a/webrtc/p2p/base/transportcontroller.h
+++ b/webrtc/p2p/base/transportcontroller.h
@@ -24,6 +24,7 @@
 
 namespace rtc {
 class Thread;
+struct PacketTransport;
 }
 namespace webrtc {
 class MetricsObserverInterface;
@@ -204,7 +205,7 @@ class TransportController : public sigslot::has_slots<>,
   bool GetStats_n(const std::string& transport_name, TransportStats* stats);
 
   // Handlers for signals from Transport.
-  void OnChannelWritableState_n(TransportChannel* channel);
+  void OnChannelWritableState_n(rtc::PacketTransport* pt);

[pthatcher1, 2016/10/13 20:26:38]

This could probably still be a TransportChannel*.  All the others are, and the
method is "OnChannelX".

[johan, 2016/10/14 16:09:33]

Acknowledged.

   void OnChannelReceivingState_n(TransportChannel* channel);
   void OnChannelGatheringState_n(TransportChannelImpl* channel);
   void OnChannelCandidateGathered_n(TransportChannelImpl* channel,