AcceleratorProvider: Make GetAcceleratorForCommandId const.

chrome/browser/renderer_context_menu/open_with_menu_factory_ash.cc

 // Copyright 2016 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 "chrome/browser/renderer_context_menu/open_with_menu_factory_ash.h"
 
 #include <algorithm>
 #include <memory>
 #include <unordered_map>
 #include <utility>
@@ skipping 19 matching lines @@
   return false;
 }
 
 bool OpenWithMenuObserver::SubMenuDelegate::IsCommandIdEnabled(
     int command_id) const {
   return true;
 }
 
 bool OpenWithMenuObserver::SubMenuDelegate::GetAcceleratorForCommandId(
     int command_id,
-    ui::Accelerator* accelerator) {
+    ui::Accelerator* accelerator) const {
   return false;
 }
 
 void OpenWithMenuObserver::SubMenuDelegate::ExecuteCommand(int command_id,
                                                            int event_flags) {
   parent_->ExecuteCommand(command_id);
 }
 
 OpenWithMenuObserver::OpenWithMenuObserver(RenderViewContextMenuProxy* proxy)
     : proxy_(proxy),
@@ skipping 138 matching lines @@
     }
   }
 
   return std::make_pair(std::move(handler_map), submenu_parent_command_id);
 }
 
 RenderViewContextMenuObserver* OpenWithMenuFactory::CreateMenu(
     RenderViewContextMenuProxy* proxy) {
   return new OpenWithMenuObserver(proxy);
 }