AcceleratorProvider: Make GetAcceleratorForCommandId const.

ash/shell/context_menu.cc

 // 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.
 
 #include "ash/shell/context_menu.h"
 
 #include "ash/common/shelf/shelf_types.h"
 #include "ash/common/shelf/wm_shelf.h"
 #include "grit/ash_strings.h"
 
@@ skipping 17 matching lines @@
 bool ContextMenu::IsCommandIdChecked(int command_id) const {
   if (command_id == MENU_AUTO_HIDE)
     return wm_shelf_->GetAutoHideBehavior() == SHELF_AUTO_HIDE_BEHAVIOR_ALWAYS;
   return false;
 }
 
 bool ContextMenu::IsCommandIdEnabled(int command_id) const {
   return true;
 }
 
-bool ContextMenu::GetAcceleratorForCommandId(int command_id,
-                                             ui::Accelerator* accelerator) {
+bool ContextMenu::GetAcceleratorForCommandId(
+    int command_id,
+    ui::Accelerator* accelerator) const {
   return false;
 }
 
 void ContextMenu::ExecuteCommand(int command_id, int event_flags) {
   if (command_id == MENU_AUTO_HIDE) {
     wm_shelf_->SetAutoHideBehavior(wm_shelf_->GetAutoHideBehavior() ==
                                            SHELF_AUTO_HIDE_BEHAVIOR_ALWAYS
                                        ? SHELF_AUTO_HIDE_BEHAVIOR_NEVER
                                        : SHELF_AUTO_HIDE_BEHAVIOR_ALWAYS);
   }
 }
 
 }  // namespace shell
 }  // namespace ash