Remove BaseChannel's dependency on TransportController.

webrtc/api/webrtcsession.h

Index: webrtc/api/webrtcsession.h
diff --git a/webrtc/api/webrtcsession.h b/webrtc/api/webrtcsession.h
index e346112cba3d9d6c2e8b7efd8c551a2b0b156d0a..42e0e4bc0d433b4bf2390477521c8dfbd1d832b8 100644
--- a/webrtc/api/webrtcsession.h
+++ b/webrtc/api/webrtcsession.h
@@ -553,6 +553,12 @@ class WebRtcSession :
 
   const std::string GetTransportName(const std::string& content_name);
 
+  void DestroyTransport(const std::string& transport_name, int component);
+  void OnDestroyRtcpTransport_n(const std::string& transport_name);
+  void DestroyVideoChannel();
+  void DestroyVoiceChannel();
+  void DestroyDataChannel();
+
   rtc::Thread* const network_thread_;
   rtc::Thread* const worker_thread_;
   rtc::Thread* const signaling_thread_;