Remove some dead code in SVG "mixins"

third_party/WebKit/Source/core/svg/SVGGraphicsElement.h

 /*
  * Copyright (C) 2004, 2005, 2008 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007 Rob Buis <buis@kde.org>
  * Copyright (C) 2014 Google, Inc.
  *
  * 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 43 matching lines @@
     SVGElement* farthestViewportElement() const;
 
     AffineTransform localCoordinateSpaceTransform(SVGElement::CTMScope) const override { return calculateAnimatedLocalTransform(); }
     bool hasAnimatedLocalTransform() const;
     AffineTransform calculateAnimatedLocalTransform() const;
     AffineTransform* animateMotionTransform() override;
 
     virtual FloatRect getBBox();
     PassRefPtrWillBeRawPtr<SVGRectTearOff> getBBoxFromJavascript();
 
-    bool isValid() const final { return SVGTests::isValid(document()); }
+    bool isValid() const final { return SVGTests::isValid(); }
 
     SVGAnimatedTransformList* transform() { return m_transform.get(); }
     const SVGAnimatedTransformList* transform() const { return m_transform.get(); }
 
     AffineTransform computeCTM(SVGElement::CTMScope mode, SVGGraphicsElement::StyleUpdateStrategy,
         const SVGGraphicsElement* ancestor = 0) const;
 
     DECLARE_VIRTUAL_TRACE();
 
 protected:
@@ skipping 12 matching lines @@
 inline bool isSVGGraphicsElement(const SVGElement& element)
 {
     return element.isSVGGraphicsElement();
 }
 
 DEFINE_SVGELEMENT_TYPE_CASTS_WITH_FUNCTION(SVGGraphicsElement);
 
 } // namespace blink
 
 #endif // SVGGraphicsElement_h