Revert of make the DtlsTransportWrapper inherit form DtlsTransportInternal

webrtc/p2p/base/packettransportinterface.h

Index: webrtc/p2p/base/packettransportinterface.h
diff --git a/webrtc/p2p/base/packettransportinterface.h b/webrtc/p2p/base/packettransportinterface.h
index 04130ef040b811cb726da637addad134ed587c5f..d0665bc1db07d23a66b8684531e68bbd6f9007fd 100644
--- a/webrtc/p2p/base/packettransportinterface.h
+++ b/webrtc/p2p/base/packettransportinterface.h
@@ -14,8 +14,6 @@
 #include <string>
 #include <vector>
 
-// This is included for PacketOptions.
-#include "webrtc/base/asyncpacketsocket.h"
 #include "webrtc/base/sigslot.h"
 #include "webrtc/base/socket.h"
 
@@ -33,7 +31,7 @@
   virtual ~PacketTransportInterface() {}
 
   // Identify the object for logging and debug purpose.
-  virtual std::string debug_name() const = 0;
+  virtual const std::string debug_name() const = 0;
 
   // The transport has been established.
   virtual bool writable() const = 0;