Fix const correctness of containerForRepaint

Source/core/rendering/LayoutRepainter.cpp

 /*
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  *           (C) 2000 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  *           (C) 2004 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Google Inc. 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 13 matching lines @@
  */
 
 #include "config.h"
 #include "core/rendering/LayoutRepainter.h"
 
 #include "core/rendering/RenderLayer.h"
 #include "core/rendering/RenderObject.h"
 
 namespace WebCore {
 
-LayoutRepainter::LayoutRepainter(RenderObject& object, bool checkForRepaint)
+LayoutRepainter::LayoutRepainter(const RenderObject& object, bool checkForRepaint)
     : m_object(object)
     , m_repaintContainer(0)
     , m_checkForRepaint(checkForRepaint)
 {
     if (RuntimeEnabledFeatures::repaintAfterLayoutEnabled())
         return;
 
     if (m_checkForRepaint) {
         m_repaintContainer = m_object.containerForRepaint();
         {
@@ skipping 10 matching lines @@
     if (RuntimeEnabledFeatures::repaintAfterLayoutEnabled())
         return false;
 
     // Hits in compositing/video/video-controls-layer-creation.html
     DisableCompositingQueryAsserts disabler;
 
     return m_checkForRepaint ? m_object.repaintAfterLayoutIfNeeded(m_repaintContainer, m_object.selfNeedsLayout(), m_oldBounds, m_oldOffset) : false;
 }
 
 } // namespace WebCore