AcceleratorProvider: Make GetAcceleratorForCommandId const.

chrome/browser/ui/toolbar/recent_tabs_sub_menu_model.h

 // Copyright 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 CHROME_BROWSER_UI_TOOLBAR_RECENT_TABS_SUB_MENU_MODEL_H_
 #define CHROME_BROWSER_UI_TOOLBAR_RECENT_TABS_SUB_MENU_MODEL_H_
 
 #include <set>
 
 #include "base/macros.h"
@@ skipping 49 matching lines @@
   // profile will be used. Testing may require a specific |open_tabs_delegate|.
   RecentTabsSubMenuModel(ui::AcceleratorProvider* accelerator_provider,
                          Browser* browser,
                          sync_driver::OpenTabsUIDelegate* open_tabs_delegate);
   ~RecentTabsSubMenuModel() override;
 
   // Overridden from ui::SimpleMenuModel::Delegate:
   bool IsCommandIdChecked(int command_id) const override;
   bool IsCommandIdEnabled(int command_id) const override;
   bool GetAcceleratorForCommandId(int command_id,
-                                  ui::Accelerator* accelerator) override;
+                                  ui::Accelerator* accelerator) const override;
   void ExecuteCommand(int command_id, int event_flags) override;
   const gfx::FontList* GetLabelFontListAt(int index) const override;
 
   int GetMaxWidthForItemAtIndex(int item_index) const;
   bool GetURLAndTitleForItemAtIndex(int index,
                                     std::string* url,
                                     base::string16* title);
 
  private:
   struct TabNavigationItem;
@@ skipping 96 matching lines @@
 
   // Time the menu is open for until a recent tab is selected.
   base::ElapsedTimer menu_opened_timer_;
 
   base::WeakPtrFactory<RecentTabsSubMenuModel> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RecentTabsSubMenuModel);
 };
 
 #endif  // CHROME_BROWSER_UI_TOOLBAR_RECENT_TABS_SUB_MENU_MODEL_H_