Revert 273652 "Host extensions"

trunk/src/remoting/host/host_extension_session.h

-// Copyright 2014 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_HOST_HOST_EXTENSION_SESSION_H_
-#define REMOTING_HOST_HOST_EXTENSION_SESSION_H_
-
-namespace remoting {
-
-namespace protocol {
-class ExtensionMessage;
-}  // namespace protocol
-
-class ClientSession;
-
-// Created by an |HostExtension| to store |ClientSession| specific state, and to
-// handle extension messages.
-class HostExtensionSession {
- public:
-  virtual ~HostExtensionSession() {}
-
-  // Called when the host receives an |ExtensionMessage| for the |ClientSession|
-  // associated with this |HostExtensionSession|.
-  // It returns |true| if the message was handled, and |false| otherwise.
-  virtual bool OnExtensionMessage(
-      ClientSession* client_session,
-      const protocol::ExtensionMessage& message) = 0;
-};
-
-}  // namespace remoting
-
-#endif  // REMOTING_HOST_HOST_EXTENSION_SESSION_H_
-