Revert "Delete paint invalidaiton code in RenderLayerModelObject::styleWillChange."

Source/core/rendering/RenderLayerModelObject.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 Apple Inc. All rights reserved.
  * Copyright (C) 2010, 2012 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 83 matching lines @@
     // we need to dirty our stacking context's z-order list.
     RenderStyle* oldStyle = style();
     if (oldStyle) {
         // Do a repaint with the old style first through RenderLayerRepainter.
         // RenderObject::styleWillChange takes care of repainting objects without RenderLayers.
         if (parent() && diff.needsRepaintLayer()) {
             layer()->repainter().repaintIncludingNonCompositingDescendants();
             if (oldStyle->hasClip() != newStyle.hasClip()
                 || oldStyle->clip() != newStyle.clip())
                 layer()->clipper().clearClipRectsIncludingDescendants();
+        } else if (diff.needsFullLayout()) {
+            if (hasLayer()) {
+                if (!layer()->hasCompositedLayerMapping() && oldStyle->position() != newStyle.position())
+                    layer()->repainter().repaintIncludingNonCompositingDescendants();
+            } else if (newStyle.hasTransform() || newStyle.opacity() < 1 || newStyle.hasFilter()) {
+                // If we don't have a layer yet, but we are going to get one because of transform or opacity,
+                //  then we need to repaint the old position of the object.
+                paintInvalidationForWholeRenderer();
+            }
         }
     }
 
     RenderObject::styleWillChange(diff, newStyle);
 }
 
 void RenderLayerModelObject::styleDidChange(StyleDifference diff, const RenderStyle* oldStyle)
 {
     bool hadTransform = hasTransform();
 
@@ skipping 58 matching lines @@
             // savings.
             layer()->addLayerHitTestRects(rects);
         }
     } else {
         RenderObject::addLayerHitTestRects(rects, currentLayer, layerOffset, containerRect);
     }
 }
 
 } // namespace WebCore