Revert "Make compositingState explicit (re-land #2 with bogus ASSERT removed)"

Source/core/rendering/RenderWidget.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2000 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2006, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2013 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
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 137 matching lines @@
 
     m_clipRect = clipRect;
 
     RefPtr<RenderWidget> protector(this);
     RefPtr<Node> protectedNode(node());
     m_widget->setFrameRect(newFrame);
 
     if (clipChanged && !frameRectChanged)
         m_widget->clipRectChanged();
 
-    if (hasLayer() && layer()->compositingState() == PaintsIntoOwnBacking)
+    if (hasLayer() && layer()->isComposited())
         layer()->compositedLayerMapping()->updateAfterWidgetResize();
 
     bool boundsChanged = m_widget->frameRect().size() != newFrame.size();
     return boundsChanged;
 }
 
 bool RenderWidget::updateWidgetGeometry()
 {
     LayoutRect contentBox = contentBoxRect();
     LayoutRect absoluteContentBox(localToAbsoluteQuad(FloatQuad(contentBox)).boundingBox());
@@ skipping 204 matching lines @@
 CursorDirective RenderWidget::getCursor(const LayoutPoint& point, Cursor& cursor) const
 {
     if (widget() && widget()->isPluginView()) {
         // A plug-in is responsible for setting the cursor when the pointer is over it.
         return DoNotSetCursor;
     }
     return RenderReplaced::getCursor(point, cursor);
 }
 
 } // namespace WebCore