AcceleratorProvider: Make GetAcceleratorForCommandId const.

ui/app_list/app_list_menu.cc

 // Copyright 2013 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 "ui/app_list/app_list_menu.h"
 
 #include <stddef.h>
 
 #include "build/build_config.h"
 #include "ui/app_list/app_list_view_delegate.h"
@@ skipping 55 matching lines @@
   return users_[command_id - SELECT_PROFILE].active;
 #else
   return false;
 #endif
 }
 
 bool AppListMenu::IsCommandIdEnabled(int command_id) const {
   return true;
 }
 
-bool AppListMenu::GetAcceleratorForCommandId(int command_id,
-                                             ui::Accelerator* accelerator) {
+bool AppListMenu::GetAcceleratorForCommandId(
+    int command_id,
+    ui::Accelerator* accelerator) const {
   return false;
 }
 
 void AppListMenu::ExecuteCommand(int command_id, int event_flags) {
   if (command_id >= SELECT_PROFILE) {
     delegate_->ShowForProfileByPath(
         users_[command_id - SELECT_PROFILE].profile_path);
     return;
   }
   switch (command_id) {
     case SHOW_SETTINGS:
       delegate_->OpenSettings();
       break;
     case SHOW_HELP:
       delegate_->OpenHelp();
       break;
     case SHOW_FEEDBACK:
       delegate_->OpenFeedback();
       break;
     default:
       NOTREACHED();
   }
 }
 
 }  // namespace app_list