Revert of Remove InputMethodEventHandler.

ash/ime/input_method_event_handler.h

+// Copyright 2015 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 ASH_IME_INPUT_METHOD_EVENT_HANDLER_H_
+#define ASH_IME_INPUT_METHOD_EVENT_HANDLER_H_
+
+#include "ash/ash_export.h"
+#include "base/macros.h"
+#include "ui/events/event_handler.h"
+
+namespace ui {
+class InputMethod;
+class KeyEvent;
+}
+
+namespace ash {
+
+// An EventHandler
+class ASH_EXPORT InputMethodEventHandler : public ui::EventHandler {
+ public:
+  explicit InputMethodEventHandler(ui::InputMethod* input_method);
+  ~InputMethodEventHandler() override;
+
+  // True to skip sending event to the InputMethod. This is used
+  // to process event passed from |DispatchKeyEventPostIME|.
+  void SetPostIME(bool post_ime);
+
+ private:
+  // Overridden from ui::EventHandler:
+  void OnKeyEvent(ui::KeyEvent* event) override;
+
+  ui::InputMethod* input_method_;
+
+  bool post_ime_;
+
+  DISALLOW_COPY_AND_ASSIGN(InputMethodEventHandler);
+};
+
+}  // namespace ash
+
+#endif  // ASH_INPUT_METHOD_EVENT_HANDLER_H_