Make RenderObject::style() return a const object

Source/core/svg/SVGSVGElement.h

 /*
  * Copyright (C) 2004, 2005, 2006 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2010 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 112 matching lines @@
 
 private:
     explicit SVGSVGElement(Document&);
     virtual ~SVGSVGElement();
 
     virtual void parseAttribute(const QualifiedName&, const AtomicString&) override;
     virtual bool isPresentationAttribute(const QualifiedName&) const override;
     virtual void collectStyleForPresentationAttribute(const QualifiedName&, const AtomicString&, MutableStylePropertySet*) override;
 
     virtual bool rendererIsNeeded(const RenderStyle&) override;
-    virtual RenderObject* createRenderer(RenderStyle*) override;
+    virtual RenderObject* createRenderer(const RenderStyle*) override;
 
     virtual InsertionNotificationRequest insertedInto(ContainerNode*) override;
     virtual void removedFrom(ContainerNode*) override;
 
     virtual void svgAttributeChanged(const QualifiedName&) override;
 
     virtual bool selfHasRelativeLengths() const override;
 
     void inheritViewAttributes(SVGViewElement*);
 
@@ skipping 20 matching lines @@
     RefPtrWillBeMember<SMILTimeContainer> m_timeContainer;
     RefPtrWillBeMember<SVGPoint> m_translation;
     RefPtrWillBeMember<SVGViewSpec> m_viewSpec;
 
     friend class SVGCurrentTranslateTearOff;
 };
 
 } // namespace blink
 
 #endif // SVGSVGElement_h