Revert 206507 "Move message_pump to base/message_loop."

trunk/src/base/message_loop/message_pump_observer.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 BASE_MESSAGE_LOOP_MESSAGE_PUMP_OBSERVER_H
-#define BASE_MESSAGE_LOOP_MESSAGE_PUMP_OBSERVER_H
-
-#include "base/base_export.h"
-#include "base/event_types.h"
-
-namespace base {
-
-enum EventStatus {
-  EVENT_CONTINUE,    // The event should be dispatched as normal.
-#if defined(USE_X11)
-  EVENT_HANDLED      // The event should not be processed any farther.
-#endif
-};
-
-// A MessagePumpObserver is an object that receives global
-// notifications from the UI MessageLoop with MessagePumpWin or
-// MessagePumpAuraX11.
-//
-// NOTE: An Observer implementation should be extremely fast!
-//
-// For use with MessagePumpAuraX11, please see message_pump_glib.h for more
-// info about how this is invoked in this environment.
-class BASE_EXPORT MessagePumpObserver {
- public:
-  // This method is called before processing a NativeEvent. If the
-  // method returns EVENT_HANDLED, it indicates the event has already
-  // been handled, so the event is not processed any farther. If the
-  // method returns EVENT_CONTINUE, the event dispatching proceeds as
-  // normal.
-  virtual EventStatus WillProcessEvent(const NativeEvent& event) = 0;
-
-  // This method is called after processing a message. This method
-  // will not be called if WillProcessEvent returns EVENT_HANDLED.
-  virtual void DidProcessEvent(const NativeEvent& event) = 0;
-
- protected:
-  virtual ~MessagePumpObserver() {}
-};
-
-}  // namespace base
-
-#endif  // BASE_MESSAGE_LOOP_MESSAGE_PUMP_OBSERVER_H