Make RenderObject::style() return a const object

Source/core/rendering/svg/SVGRenderingContext.cpp

 /*
  * Copyright (C) 2007, 2008 Rob Buis <buis@kde.org>
  * Copyright (C) 2007 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2007 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2009 Google, Inc.  All rights reserved.
  * Copyright (C) 2009 Dirk Schulze <krit@webkit.org>
  * 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
@@ skipping 91 matching lines @@
 }
 
 void SVGRenderingContext::applyCompositingIfNecessary()
 {
     ASSERT(!m_paintInfo.isRenderingClipPathAsMaskImage());
 
     // RenderLayer takes care of root opacity and blend mode.
     if (m_object->isSVGRoot())
         return;
 
-    RenderStyle* style = m_object->style();
+    const RenderStyle* style = m_object->style();
     ASSERT(style);
     float opacity = style->opacity();
     bool hasBlendMode = style->hasBlendMode() && m_object->isBlendingAllowed();
     if (opacity < 1 || hasBlendMode) {
         m_clipRecorder = adoptPtr(new FloatClipRecorder(*m_paintInfo.context, m_object->displayItemClient(), m_paintInfo.phase, m_object->paintInvalidationRectInLocalCoordinates()));
         WebBlendMode blendMode = hasBlendMode ? style->blendMode() : WebBlendModeNormal;
         CompositeOperator compositeOp = hasBlendMode ? CompositeSourceOver : m_paintInfo.context->compositeOperationDeprecated();
         m_compositingRecorder = adoptPtr(new CompositingRecorder(m_paintInfo.context, m_object->displayItemClient(), compositeOp, blendMode, opacity, compositeOp));
     }
 }
@@ skipping 127 matching lines @@
 {
     ASSERT(context);
     ASSERT(item);
     ASSERT(!item->needsLayout());
 
     PaintInfo info(context, LayoutRect::infiniteIntRect(), PaintPhaseForeground, PaintBehaviorNormal);
     item->paint(info, IntPoint());
 }
 
 } // namespace blink