Unify the GlobalEventHandlers list on the C++ side

Source/core/html/HTMLBodyElement.idl

 /*
  * Copyright (C) 2006, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Samuel Weinig <sam.weinig@gmail.com>
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 21 matching lines @@
     attribute EventHandler onmessage;
     attribute EventHandler onoffline;
     attribute EventHandler ononline;
     attribute EventHandler onpopstate;
     attribute EventHandler onresize;
     attribute EventHandler onstorage;
     attribute EventHandler onunload;
 
     [Conditional=ORIENTATION_EVENTS] attribute EventHandler onorientationchange;
 
-    // Overrides of Element attributes (with different implementation in bindings).
+    // Overrides of GlobalEventHandler attributes
     attribute EventHandler onblur;
     attribute EventHandler onerror;
     attribute EventHandler onfocus;
     attribute EventHandler onload;
+    attribute EventHandler onscroll;
 
     // Not implemented yet.
     // attribute EventHandler onafterprint;
     // attribute EventHandler onbeforeprint;
     // attribute EventHandler onredo;
     // attribute EventHandler onundo;
 };