base: Remove now-unused MessagePumpObserver.

base/message_loop/message_pump_observer.h

Index: base/message_loop/message_pump_observer.h
diff --git a/base/message_loop/message_pump_observer.h b/base/message_loop/message_pump_observer.h
deleted file mode 100644
index d6e7abf786adab9d685e0d616cebd8e32a665358..0000000000000000000000000000000000000000
--- a/base/message_loop/message_pump_observer.h
+++ /dev/null
@@ -1,35 +0,0 @@
-// 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"
-
-#if !defined(OS_WIN)
-#error Should not be here.
-#endif
-
-namespace base {
-
-// A MessagePumpObserver is an object that receives global
-// notifications from the UI MessageLoop with MessagePumpWin.
-//
-// NOTE: An Observer implementation should be extremely fast!
-class BASE_EXPORT MessagePumpObserver {
- public:
-  // This method is called before processing a NativeEvent.
-  virtual void WillProcessEvent(const NativeEvent& event) = 0;
-
-  // This method is called after processing a message.
-  virtual void DidProcessEvent(const NativeEvent& event) = 0;
-
- protected:
-  virtual ~MessagePumpObserver() {}
-};
-
-}  // namespace base
-
-#endif  // BASE_MESSAGE_LOOP_MESSAGE_PUMP_OBSERVER_H