Make RenderObject::style() return a const object

Source/core/rendering/svg/RenderSVGResourceMasker.cpp

 /*
  * Copyright (C) Research In Motion Limited 2009-2010. 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.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 116 matching lines @@
 
     // Using strokeBoundingBox (instead of paintInvalidationRectInLocalCoordinates) to avoid the intersection
     // with local clips/mask, which may yield incorrect results when mixing objectBoundingBox and
     // userSpaceOnUse units (http://crbug.com/294900).
     FloatRect bounds = strokeBoundingBox();
     context->beginRecording(bounds);
     for (SVGElement* childElement = Traversal<SVGElement>::firstChild(*element()); childElement; childElement = Traversal<SVGElement>::nextSibling(*childElement)) {
         RenderObject* renderer = childElement->renderer();
         if (!renderer)
             continue;
-        RenderStyle* style = renderer->style();
+        const RenderStyle* style = renderer->style();
         if (!style || style->display() == NONE || style->visibility() != VISIBLE)
             continue;
 
         SVGRenderingContext::renderSubtree(context, renderer);
     }
     m_maskContentPicture = context->endRecording();
 }
 
 void RenderSVGResourceMasker::calculateMaskContentPaintInvalidationRect()
 {
     for (SVGElement* childElement = Traversal<SVGElement>::firstChild(*element()); childElement; childElement = Traversal<SVGElement>::nextSibling(*childElement)) {
         RenderObject* renderer = childElement->renderer();
         if (!renderer)
             continue;
-        RenderStyle* style = renderer->style();
+        const RenderStyle* style = renderer->style();
         if (!style || style->display() == NONE || style->visibility() != VISIBLE)
              continue;
         m_maskContentBoundaries.unite(renderer->localToParentTransform().mapRect(renderer->paintInvalidationRectInLocalCoordinates()));
     }
 }
 
 FloatRect RenderSVGResourceMasker::resourceBoundingBox(const RenderObject* object)
 {
     SVGMaskElement* maskElement = toSVGMaskElement(element());
     ASSERT(maskElement);
@@ skipping 14 matching lines @@
         transform.translate(objectBoundingBox.x(), objectBoundingBox.y());
         transform.scaleNonUniform(objectBoundingBox.width(), objectBoundingBox.height());
         maskRect = transform.mapRect(maskRect);
     }
 
     maskRect.intersect(maskBoundaries);
     return maskRect;
 }
 
 }