Make RenderObject::style() return a const object

Source/core/html/HTMLMeterElement.cpp

 /*
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
  *
  * 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 37 matching lines @@
 {
 }
 
 PassRefPtrWillBeRawPtr<HTMLMeterElement> HTMLMeterElement::create(Document& document)
 {
     RefPtrWillBeRawPtr<HTMLMeterElement> meter = adoptRefWillBeNoop(new HTMLMeterElement(document));
     meter->ensureUserAgentShadowRoot();
     return meter.release();
 }
 
-RenderObject* HTMLMeterElement::createRenderer(RenderStyle* style)
+RenderObject* HTMLMeterElement::createRenderer(const RenderStyle* style)
 {
     if (hasAuthorShadowRoot() || !LayoutTheme::theme().supportsMeter(style->appearance()))
         return RenderObject::createObject(this, style);
 
     return new RenderMeter(this);
 }
 
 void HTMLMeterElement::parseAttribute(const QualifiedName& name, const AtomicString& value)
 {
     if (name == valueAttr || name == minAttr || name == maxAttr || name == lowAttr || name == highAttr || name == optimumAttr)
@@ skipping 143 matching lines @@
     inner->appendChild(bar);
 }
 
 void HTMLMeterElement::trace(Visitor* visitor)
 {
     visitor->trace(m_value);
     LabelableElement::trace(visitor);
 }
 
 } // namespace