Revert of Make P2PTransportChannel inherit from IceTransportInternal.

webrtc/p2p/base/icetransportinternal.h

Index: webrtc/p2p/base/icetransportinternal.h
diff --git a/webrtc/p2p/base/icetransportinternal.h b/webrtc/p2p/base/icetransportinternal.h
index e48b36ad10aee007cd562de3c0797875a77f3d9e..4c47a140a5145103bf1d259ccecdf5368d4fd7ea 100644
--- a/webrtc/p2p/base/icetransportinternal.h
+++ b/webrtc/p2p/base/icetransportinternal.h
@@ -25,12 +25,11 @@
 
 namespace cricket {
 
-// TODO(zhihuang): replace it with PeerConnectionInterface::IceConnectionState.
-enum class IceTransportState {
+enum class TransportState {
   STATE_INIT,
   STATE_CONNECTING,  // Will enter this state once a connection is created
   STATE_COMPLETED,
-  STATE_FAILED
+  STATE_FAILEDs
 };
 
 // TODO(zhihuang): Remove this once it's no longer used in
@@ -45,9 +44,9 @@
 // the IceTransportInterface will be split from this class.
 class IceTransportInternal : public rtc::PacketTransportInterface {
  public:
-  virtual ~IceTransportInternal(){};
+  virtual ~IceTransportInternal();
 
-  virtual IceTransportState GetState() const = 0;
+  virtual TransportState GetState() const = 0;
 
   virtual const std::string& transport_name() const = 0;
 
@@ -96,9 +95,6 @@
 
   virtual IceGatheringState gathering_state() const = 0;
 
-  // Returns the current stats for this connection.
-  virtual bool GetStats(ConnectionInfos* infos) = 0;
-
   sigslot::signal1<IceTransportInternal*> SignalGatheringState;
 
   // Handles sending and receiving of candidates.
@@ -123,20 +119,11 @@
   sigslot::signal4<IceTransportInternal*, CandidatePairInterface*, int, bool>
       SignalSelectedCandidatePairChanged;
 
-  // Invoked when there is conflict in the ICE role between local and remote
-  // agents.
-  sigslot::signal1<IceTransportInternal*> SignalRoleConflict;
-
-  // Emitted whenever the transport state changed.
-  sigslot::signal1<IceTransportInternal*> SignalStateChanged;
-
   // Invoked when the transport is being destroyed.
   sigslot::signal1<IceTransportInternal*> SignalDestroyed;
 
   // Debugging description of this transport.
-  std::string debug_name() const override {
-    return transport_name() + " " + std::to_string(component());
-  }
+  std::string ToString() const;
 };
 
 }  // namespace cricket