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

Source/core/page/DOMWindow.idl

 /*
  * Copyright (C) 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2011 Google 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 156 matching lines @@
     [DoNotCheckSecurity, Custom, RaisesException] void postMessage(SerializedScriptValue message, DOMString targetOrigin, optional Array messagePorts);
 
     [Replaceable] readonly attribute Performance performance;
 
     // Timers
     [Custom] long setTimeout(any handler, [Default=Undefined] optional long timeout);
     void clearTimeout([Default=Undefined] optional long handle);
     [Custom] long setInterval(any handler, [Default=Undefined] optional long timeout);
     void clearInterval([Default=Undefined] optional long handle);
 
-    [MeasureAs=UnprefixedRequestAnimationFrame] long requestAnimationFrame([Callback] RequestAnimationFrameCallback callback);
+    [MeasureAs=UnprefixedRequestAnimationFrame] long requestAnimationFrame(RequestAnimationFrameCallback callback);
     void cancelAnimationFrame(long id);
-    [MeasureAs=PrefixedRequestAnimationFrame] long webkitRequestAnimationFrame([Callback] RequestAnimationFrameCallback callback);
+    [MeasureAs=PrefixedRequestAnimationFrame] long webkitRequestAnimationFrame(RequestAnimationFrameCallback callback);
     [ImplementedAs=cancelAnimationFrame] void webkitCancelAnimationFrame(long id);
     [ImplementedAs=cancelAnimationFrame] void webkitCancelRequestAnimationFrame(long id); // This is a deprecated alias for webkitCancelAnimationFrame(). Remove this when removing vendor prefix.
 
     // Base64
     [RaisesException] DOMString atob([TreatNullAs=NullString,Default=Undefined] optional DOMString string);
     [RaisesException] DOMString btoa([TreatNullAs=NullString,Default=Undefined] optional DOMString string);
 
     [Replaceable] attribute DOMWindowCSS CSS;
 
     // Events
@@ skipping 560 matching lines @@
     attribute MutationRecordConstructor MutationRecord;
 
     [EnabledAtRuntime=mediaSource] attribute MediaSourceConstructor WebKitMediaSource;
     [EnabledAtRuntime=mediaSource] attribute SourceBufferConstructor WebKitSourceBuffer;
     [EnabledAtRuntime=mediaSource] attribute SourceBufferListConstructor WebKitSourceBufferList;
 
     // window.toString() requires special handling in V8
     [DoNotCheckSignature, DoNotCheckSecurity, Custom, NotEnumerable] DOMString toString();
 };