Make sure manifest specified shortcut for Extension Command can not override the built-in shortcuts.

chrome/browser/extensions/extension_keybinding_registry.h

 // 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.
 
 #ifndef CHROME_BROWSER_EXTENSIONS_EXTENSION_KEYBINDING_REGISTRY_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_KEYBINDING_REGISTRY_H_
 
 #include <string>
 
 #include "base/compiler_specific.h"
 #include "content/public/browser/notification_details.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 #include "content/public/browser/notification_source.h"
 
 class Profile;
 
+namespace ui {
+class Accelerator;
+}

[Finnur, 2013/04/15 14:30:31]

Already removed locally.

+
 namespace extensions {
 
 class ActiveTabPermissionGranter;
 class Extension;
 
 // The ExtensionKeybindingRegistry is a class that handles the cross-platform
 // logic for keyboard accelerators. See platform-specific implementations for
 // implementation details for each platform.
 class ExtensionKeybindingRegistry : public content::NotificationObserver {
  public:
@@ skipping 65 matching lines @@
 
   // Weak pointer to our delegate. Not owned by us. Must outlive this class.
   Delegate* delegate_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionKeybindingRegistry);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_KEYBINDING_REGISTRY_H_