Remove custom element type extensions.

sky/engine/core/dom/Document.idl

 /*
  * Copyright (C) 2006, 2007, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2006, 2007 Samuel Weinig <sam@webkit.org>
  *
  * 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 69 matching lines @@
                                              [Default=Undefined] optional double pageY,
                                              [Default=Undefined] optional double screenX,
                                              [Default=Undefined] optional double screenY,
                                              [Default=Undefined] optional double radiusX,
                                              [Default=Undefined] optional double radiusY,
                                              [Default=Undefined] optional float rotationAngle,
                                              [Default=Undefined] optional float force);
     [RuntimeEnabled=Touch] TouchList createTouchList(Touch... touches);
 
     [CallWith=ScriptState, CustomElementCallbacks, RaisesException, MeasureAs=DocumentRegisterElement] CustomElementConstructor registerElement(DOMString name, optional Dictionary options);
-    [CustomElementCallbacks, PerWorldBindings, RaisesException] Element createElement(DOMString localName, DOMString? typeExtension);
 
     // Page visibility API.
     readonly attribute DOMString visibilityState;
     readonly attribute boolean hidden;
 
     readonly attribute HTMLScriptElement currentScript;
 };
 
 Document implements ParentNode;