Change PaintLayer::m_layoutObject to a reference.

third_party/WebKit/Source/core/layout/LayoutBox.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
  *           (C) 2005, 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc.
  *               All rights reserved.
  * Copyright (C) 2013 Adobe Systems Incorporated. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 1759 matching lines @@
     setShouldDoFullPaintInvalidation(PaintInvalidationFull);
   }
 }
 
 PaintInvalidationReason LayoutBox::invalidatePaintIfNeeded(
     const PaintInvalidationState& paintInvalidationState) {
   if (hasBoxDecorationBackground()
       // We also paint overflow controls in background phase.
       || (hasOverflowClip() && getScrollableArea()->hasOverflowControls())) {
     PaintLayer& layer = paintInvalidationState.paintingLayer();
-    if (layer.layoutObject() != this)
+    if (&layer.layoutObject() != this)
       layer.setNeedsPaintPhaseDescendantBlockBackgrounds();
   }
 
   return LayoutBoxModelObject::invalidatePaintIfNeeded(paintInvalidationState);
 }
 
 PaintInvalidationReason LayoutBox::invalidatePaintIfNeeded(
     const PaintInvalidatorContext& context) const {
   return BoxPaintInvalidator(*this, context).invalidatePaintIfNeeded();
 }
@@ skipping 3923 matching lines @@
     block->adjustChildDebugRect(rect);
 
   return rect;
 }
 
 bool LayoutBox::shouldClipOverflow() const {
   return hasOverflowClip() || styleRef().containsPaint() || hasControlClip();
 }
 
 }  // namespace blink