try 3 of: Split out InputMethodMenuManager from InputMethodManager.

ash/ime/input_method_menu_manager.h

Index: ash/ime/input_method_menu_manager.h
diff --git a/ash/ime/input_method_menu_manager.h b/ash/ime/input_method_menu_manager.h
new file mode 100644
index 0000000000000000000000000000000000000000..ffaeb480a89a6d972c14e7f941497283defb527d
--- /dev/null
+++ b/ash/ime/input_method_menu_manager.h
@@ -0,0 +1,65 @@
+// 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.
+
+#include "ash/ash_export.h"
+
+#include "ash/ime/input_method_menu_item.h"
+#include "base/observer_list.h"
+
+#ifndef ASH_IME_INPUT_METHOD_MENU_MANAGER_H_
+#define ASH_IME_INPUT_METHOD_MENU_MANAGER_H_
+
+template<typename Type> struct DefaultSingletonTraits;
+
+namespace ash {
+namespace ime {
+
+class ASH_EXPORT InputMethodMenuManager {
+public:
+  class Observer {
+   public:
+    virtual ~Observer() {}
+
+    // Called when the list of menu items is changed.
+    virtual void InputMethodMenuItemChanged(
+        InputMethodMenuManager* manager) = 0;
+  };
+
+  ~InputMethodMenuManager();
+
+  void AddObserver(Observer* observer);
+  void RemoveObserver(Observer* observer);
+
+  // Obtains the singleton instance.
+  static InputMethodMenuManager* GetInstance();
+
+  // Sets the list of input method menu items. The list could be empty().
+  void SetCurrentInputMethodMenuItemList(
+      const InputMethodMenuItemList& menu_list);
+
+  // Gets the list of input method menu items. The list could be empty().
+  InputMethodMenuItemList GetCurrentInputMethodMenuItemList() const;
+
+  // True if the key exists in the menu_list_.
+  bool HasInputMethodMenuItemForKey(const std::string& key) const;
+
+ private:
+  InputMethodMenuManager();
+
+  // For Singleton to be able to construct an instance.
+  friend struct DefaultSingletonTraits<InputMethodMenuManager>;
+
+  // Menu item list of the input method.  This is set by extension IMEs.
+  InputMethodMenuItemList menu_list_;
+
+  // Observers who will be notified when menu changes.
+  ObserverList<Observer> observers_;
+
+  DISALLOW_COPY_AND_ASSIGN(InputMethodMenuManager);
+};
+
+}  // namespace ime
+}  // namespace ash
+
+#endif // ASH_IME_INPUT_METHOD_MENU_MANAGER_H_