Get rid of [Callback] extended attribute for parameters in IDL files

Source/modules/notifications/Notification.idl

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2011, 2012 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 32 matching lines @@
 #if defined(ENABLE_LEGACY_NOTIFICATIONS) && ENABLE_LEGACY_NOTIFICATIONS
     void cancel();
 #endif
 #if defined(ENABLE_NOTIFICATIONS) && ENABLE_NOTIFICATIONS
     void close();
 #endif
 
 
 #if defined(ENABLE_NOTIFICATIONS) && ENABLE_NOTIFICATIONS
     [CallWith=ScriptExecutionContext] static readonly attribute DOMString permission;
-    [CallWith=ScriptExecutionContext] static void requestPermission([Callback] optional NotificationPermissionCallback callback);
+    [CallWith=ScriptExecutionContext] static void requestPermission(optional NotificationPermissionCallback callback);
 #endif
 
     attribute EventListener onshow;
 #if defined(ENABLE_LEGACY_NOTIFICATIONS) && ENABLE_LEGACY_NOTIFICATIONS
     attribute EventListener ondisplay;
 #endif
     attribute EventListener onerror;
     attribute EventListener onclose;
     attribute EventListener onclick;
 
 #if defined(ENABLE_LEGACY_NOTIFICATIONS) && ENABLE_LEGACY_NOTIFICATIONS
     attribute DOMString dir;
     attribute DOMString replaceId;
 #endif
 #if defined(ENABLE_NOTIFICATIONS) && ENABLE_NOTIFICATIONS
     attribute DOMString tag;
 #endif
 
     // EventTarget interface
     void addEventListener(DOMString type, 
                           EventListener listener, 
                           optional boolean useCapture);
     void removeEventListener(DOMString type, 
                              EventListener listener, 
                              optional boolean useCapture);
     [RaisesException] boolean dispatchEvent(Event evt);
 };