Add TransportContext class.

remoting/protocol/port_allocator_factory.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef REMOTING_PROTOCOL_PORT_ALLOCATOR_FACTORY_H_
 #define REMOTING_PROTOCOL_PORT_ALLOCATOR_FACTORY_H_
 
-#include "third_party/webrtc/p2p/base/portallocator.h"
+#include "base/memory/scoped_ptr.h"
+
+namespace cricket {
+class HttpPortAllocatorBase;
+}  // namespace cricket
 
 namespace remoting {
 namespace protocol {
 
 // Factory class used for creating cricket::PortAllocator that is used
 // for ICE negotiation.
 class PortAllocatorFactory {
  public:
-  virtual cricket::PortAllocator* CreatePortAllocator() = 0;
+  virtual scoped_ptr<cricket::HttpPortAllocatorBase> CreatePortAllocator() = 0;
 
   virtual ~PortAllocatorFactory() {}
 };
 
 }  // namespace protocol
 }  // namespace remoting
 
 #endif  // REMOTING_PROTOCOL_PORT_ALLOCATOR_FACTORY_H_