Revert of Make P2PTransportChannel inherit from IceTransportInternal.

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 7929cf014024ac7f4a0204bf5ace161a525c7321..a46ce00dbc329a8f4627cca1318d06139572a476 100644
--- a/webrtc/p2p/base/transportcontroller.h
+++ b/webrtc/p2p/base/transportcontroller.h
@@ -164,13 +164,13 @@
   // TODO(deadbeef): Get rid of these virtual methods. Used by
   // FakeTransportController currently, but FakeTransportController shouldn't
   // even be functioning by subclassing TransportController.
-  virtual IceTransportInternal* CreateIceTransportChannel_n(
+  virtual TransportChannelImpl* CreateIceTransportChannel_n(
       const std::string& transport_name,
       int component);
   virtual TransportChannelImpl* CreateDtlsTransportChannel_n(
       const std::string& transport_name,
       int component,
-      IceTransportInternal* ice);
+      TransportChannelImpl* ice);
 
  private:
   void OnMessage(rtc::Message* pmsg) override;