Refactor of Authenticator to allow it to ProcessMessage asynchronously and then call a callback

remoting/protocol/authenticator.h

 // Copyright (c) 2012 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_AUTHENTICATOR_H_
 #define REMOTING_PROTOCOL_AUTHENTICATOR_H_
 
 #include <string>
 
+#include "base/callback.h"
 #include "base/memory/scoped_ptr.h"
 
 namespace buzz {
 class XmlElement;
 }  // namespace buzz
 
 namespace remoting {
 namespace protocol {
 
 class ChannelAuthenticator;
@@ skipping 56 matching lines @@
 
   // Returns current state of the authenticator.
   virtual State state() const = 0;
 
   // Returns rejection reason. Can be called only when in REJECTED state.
   virtual RejectionReason rejection_reason() const = 0;
 
   // Called in response to incoming message received from the peer.
   // Should only be called when in WAITING_MESSAGE state. Caller
   // retains ownership of |message|.
-  virtual void ProcessMessage(const buzz::XmlElement* message) = 0;
+  virtual void ProcessMessage(const base::Closure& resume_callback,
+                              const buzz::XmlElement* message) = 0;
 
   // Must be called when in MESSAGE_READY state. Returns next
   // authentication message that needs to be sent to the peer.
   virtual scoped_ptr<buzz::XmlElement> GetNextMessage() = 0;
 
   // Creates new authenticator for a channel. Can be called only in
   // the ACCEPTED state.
   virtual scoped_ptr<ChannelAuthenticator>
       CreateChannelAuthenticator() const = 0;
 };
@@ skipping 15 matching lines @@
   virtual scoped_ptr<Authenticator> CreateAuthenticator(
       const std::string& local_jid,
       const std::string& remote_jid,
       const buzz::XmlElement* first_message) = 0;
 };
 
 }  // namespace protocol
 }  // namespace remoting
 
 #endif  // REMOTING_PROTOCOL_AUTHENTICATOR_H_