Make RenderObject::style() return a const object

Source/core/rendering/svg/SVGTextMetrics.cpp

 /*
  * Copyright (C) Research In Motion Limited 2010-2012. 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 46 matching lines @@
 }
 
 TextRun SVGTextMetrics::constructTextRun(RenderSVGInlineText* text, unsigned position, unsigned length)
 {
     ASSERT(text->style());
     return constructTextRun(text, position, length, text->style()->direction());
 }
 
 TextRun SVGTextMetrics::constructTextRun(RenderSVGInlineText* text, unsigned position, unsigned length, TextDirection textDirection)
 {
-    RenderStyle* style = text->style();
+    const RenderStyle* style = text->style();
     ASSERT(style);
 
     TextRun run(static_cast<const LChar*>(0) // characters, will be set below if non-zero.
                 , 0 // length, will be set below if non-zero.
                 , 0 // xPos, only relevant with allowTabs=true
                 , 0 // padding, only relevant for justified text, not relevant for SVG
                 , TextRun::AllowTrailingExpansion
                 , textDirection
                 , isOverride(style->unicodeBidi()) /* directionalOverride */);
 
@@ skipping 32 matching lines @@
     float scalingFactor = text->scalingFactor();
     ASSERT(scalingFactor);
 
     m_width = width / scalingFactor;
     m_height = text->scaledFont().fontMetrics().floatHeight() / scalingFactor;
 
     m_length = length;
 }
 
 }