AcceleratorProvider: Make GetAcceleratorForCommandId const.

chrome/browser/ui/cocoa/app_menu/app_menu_controller.mm

 // Copyright (c) 2011 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.
 
 #import "chrome/browser/ui/cocoa/app_menu/app_menu_controller.h"
 
 #include <stddef.h>
 
 #include "base/bind.h"
 #include "base/mac/bundle_locations.h"
@@ skipping 61 matching lines @@
 - (RecentTabsSubMenuModel*)recentTabsMenuModel;
 - (int)maxWidthForMenuModel:(ui::MenuModel*)model
                  modelIndex:(int)modelIndex;
 @end
 
 namespace AppMenuControllerInternal {
 
 // A C++ delegate that handles the accelerators in the app menu.
 class AcceleratorDelegate : public ui::AcceleratorProvider {
  public:
-  bool GetAcceleratorForCommandId(int command_id,
-                                  ui::Accelerator* out_accelerator) override {
+  bool GetAcceleratorForCommandId(
+      int command_id,
+      ui::Accelerator* out_accelerator) const override {
     AcceleratorsCocoa* keymap = AcceleratorsCocoa::GetInstance();
     const ui::Accelerator* accelerator =
         keymap->GetAcceleratorForCommand(command_id);
     if (!accelerator)
       return false;
     *out_accelerator = *accelerator;
     return true;
   }
 };
 
@@ skipping 536 matching lines @@
   // (and thus, after all our ability to adjust it normally). Throw in the
   // towel, and simply don't let the frame move from where it's supposed to be.
   // TODO(devlin): Yet another Cocoa hack. It'd be good to find a workaround,
   // but unlikely unless we replace the Cocoa menu implementation.
   NSView* containerSuperview = [overflowActionsContainerView_ superview];
   if (NSMinX([containerSuperview frame]) != 0)
     [containerSuperview setFrameOrigin:NSZeroPoint];
 }
 
 @end  // @implementation AppMenuButtonViewController