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

remoting/protocol/me2me_host_authenticator_factory.cc

Index: remoting/protocol/me2me_host_authenticator_factory.cc
diff --git a/remoting/protocol/me2me_host_authenticator_factory.cc b/remoting/protocol/me2me_host_authenticator_factory.cc
index ebdde5bfe2627f213c2c8c2200653dd086c1b5b3..84da6a114c6d549899faa3022c4848f453bec0c5 100644
--- a/remoting/protocol/me2me_host_authenticator_factory.cc
+++ b/remoting/protocol/me2me_host_authenticator_factory.cc
@@ -34,9 +34,11 @@ class RejectingAuthenticator : public Authenticator {
     return INVALID_CREDENTIALS;
   }
 
-  virtual void ProcessMessage(const buzz::XmlElement* message) OVERRIDE {
+  virtual void ProcessMessage(const base::Closure& resume_callback,
+                              const buzz::XmlElement* message) OVERRIDE {
     DCHECK_EQ(state_, WAITING_MESSAGE);
     state_ = REJECTED;
+    resume_callback.Run();
   }
 
   virtual scoped_ptr<buzz::XmlElement> GetNextMessage() OVERRIDE {