mac: Create a static mapping of accelerators in the main menu.

ui/base/accelerators/platform_accelerator_cocoa.h

 // 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.
 
 #ifndef UI_BASE_ACCELERATORS_PLATFORM_ACCELERATOR_COCOA_H_
 #define UI_BASE_ACCELERATORS_PLATFORM_ACCELERATOR_COCOA_H_
 
 #include <Foundation/Foundation.h>
 
 #include "base/mac/scoped_nsobject.h"
 #include "ui/base/accelerators/platform_accelerator.h"
 
 namespace ui {
 
 // This is a Mac specific class for specifing accelerator keys.
 class UI_BASE_EXPORT PlatformAcceleratorCocoa : public PlatformAccelerator {
  public:
   PlatformAcceleratorCocoa();
   PlatformAcceleratorCocoa(NSString* key_code, NSUInteger modifier_mask);
   virtual ~PlatformAcceleratorCocoa();
 
   // PlatformAccelerator:
   virtual scoped_ptr<PlatformAccelerator> CreateCopy() const OVERRIDE;
   virtual bool Equals(const PlatformAccelerator& rhs) const OVERRIDE;
 
+  // The keyEquivalent of the NSMenuItem associated with the accelerator.
   NSString* characters() const { return characters_.get(); }
+  // The keyEquivalentModifierMask of the NSMenuItem associated with the
+  // accelerator.
   NSUInteger modifier_mask() const { return modifier_mask_; }
 
  private:
   // String of characters for the key equivalent.
   base::scoped_nsobject<NSString> characters_;
   NSUInteger modifier_mask_;
 
   DISALLOW_COPY_AND_ASSIGN(PlatformAcceleratorCocoa);
 };
 
 }  // namespace ui
 
 #endif  // UI_BASE_ACCELERATORS_PLATFORM_ACCELERATOR_COCOA_H_