Make RenderObject::style() return a const object

Source/core/layout/LayoutRubyRun.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 70 matching lines @@
 LayoutRubyBase* LayoutRubyRun::rubyBaseSafe()
 {
     LayoutRubyBase* base = rubyBase();
     if (!base) {
         base = createRubyBase();
         RenderBlockFlow::addChild(base);
     }
     return base;
 }
 
-bool LayoutRubyRun::isChildAllowed(RenderObject* child, RenderStyle*) const
+bool LayoutRubyRun::isChildAllowed(RenderObject* child, const RenderStyle*) const
 {
     return child->isRubyText() || child->isInline();
 }
 
 void LayoutRubyRun::addChild(RenderObject* child, RenderObject* beforeChild)
 {
     ASSERT(child);
 
     if (child->isRubyText()) {
         if (!beforeChild) {
@@ skipping 194 matching lines @@
     // We can overhang the ruby by no more than half the width of the neighboring text
     // and no more than half the font size.
     int halfWidthOfFontSize = rubyText->style(firstLine)->fontSize() / 2;
     if (startOverhang)
         startOverhang = std::min<int>(startOverhang, std::min<int>(toRenderText(startRenderer)->minLogicalWidth(), halfWidthOfFontSize));
     if (endOverhang)
         endOverhang = std::min<int>(endOverhang, std::min<int>(toRenderText(endRenderer)->minLogicalWidth(), halfWidthOfFontSize));
 }
 
 } // namespace blink