Reduce CPU usage for input method switching.

chrome/browser/chromeos/login/keyboard_switch_menu.h

 // Copyright (c) 2010 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 CHROME_BROWSER_CHROMEOS_LOGIN_KEYBOARD_SWITCH_MENU_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_KEYBOARD_SWITCH_MENU_H_
 #pragma once
 
 #include <string>
 
 #include "base/scoped_ptr.h"
 #include "chrome/browser/chromeos/status/input_method_menu_button.h"
 #include "chrome/browser/chromeos/status/status_area_host.h"
 
 namespace chromeos {
 
 // A class for the button in the OOBE network configuration screen which expands
 // a dropdown menu for switching keyboard layout. Note that the InputMethodMenu
 // class implements the views::ViewMenuDelegate interface.
 class KeyboardSwitchMenu : public InputMethodMenu {
  public:
   KeyboardSwitchMenu();
   virtual ~KeyboardSwitchMenu() {}
 
   // InputMethodMenu::InputMethodMenuHost implementation.
-  virtual void UpdateUI(
-      const std::wstring& name, const std::wstring& tooltip);
+  virtual void UpdateUI(const std::string& input_method_id,
+                        const std::wstring& name,
+                        const std::wstring& tooltip,
+                        size_t num_active_input_methods);
   virtual bool ShouldSupportConfigUI() { return false; }
   virtual void OpenConfigUI() {}
 
   // views::ViewMenuDelegate implementation which overrides the implementation
   // in InputMethodMenu.
   virtual void RunMenu(views::View* source, const gfx::Point& pt);
 
   // Returns current keyboard name to be placed on the keyboard menu-button.
   std::wstring GetCurrentKeyboardName() const;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(KeyboardSwitchMenu);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_KEYBOARD_SWITCH_MENU_H_