Remove old Authentication code that we don't use or need.

remoting/protocol/client_stub.h

 // Copyright (c) 2011 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.
 
 // Interface of a client that receives commands from a Chromoting host.
 //
 // This interface is responsible for a subset of control messages sent to
 // the Chromoting client.
 
 #ifndef REMOTING_PROTOCOL_CLIENT_STUB_H_
 #define REMOTING_PROTOCOL_CLIENT_STUB_H_
 
 #include "base/basictypes.h"
 #include "base/callback.h"
 
 namespace remoting {
 namespace protocol {
 
-class LocalLoginStatus;
-class NotifyResolutionRequest;
-
 class ClientStub {
  public:
   ClientStub() {}
   virtual ~ClientStub() {}
 
-  virtual void BeginSessionResponse(const LocalLoginStatus* msg,
-                                    const base::Closure& done) = 0;
+  // Currently we don't use the control channel for anything. Add new
+  // message handlers here when necessary.
 
  private:
   DISALLOW_COPY_AND_ASSIGN(ClientStub);
 };
 
 }  // namespace protocol
 }  // namespace remoting
 
 #endif  // REMOTING_PROTOCOL_CLIENT_STUB_H_