WIP (Introduce WTF::NonNullPtr<T>.)

Source/core/svg/SVGSVGElement.cpp

 /*
  * Copyright (C) 2004, 2005, 2006 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2010 Rob Buis <buis@kde.org>
  * Copyright (C) 2007 Apple Inc. All rights reserved.
  *
  * 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.
  *
@@ skipping 744 matching lines @@
     if (viewElement->hasAttribute(SVGNames::zoomAndPanAttr))
         view->setZoomAndPanBaseValue(viewElement->zoomAndPan());
     else
         view->setZoomAndPanBaseValue(zoomAndPan());
 }
 
 // getElementById on SVGSVGElement is restricted to only the child subtree defined by the <svg> element.
 // See http://www.w3.org/TR/SVG11/struct.html#InterfaceSVGSVGElement
 Element* SVGSVGElement::getElementById(const AtomicString& id) const
 {
-    Element* element = treeScope().getElementById(id);
+    Element* element = treeScope()->getElementById(id);
     if (element && element->isDescendantOf(this))
         return element;
 
     // Fall back to traversing our subtree. Duplicate ids are allowed, the first found will
     // be returned.
     for (Node* node = firstChild(); node; node = NodeTraversal::next(node, this)) {
         if (!node->isElementNode())
             continue;
 
         Element* element = toElement(node);
         if (element->getIdAttribute() == id)
             return element;
     }
     return 0;
 }
 
 }