Refactoring DrawLooper so that it can apply shadow effects as skia image filters

Source/core/rendering/RenderBoxModelObject.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 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 2495 matching lines @@
                             rectToClipOut.inflate(-1);
                     }
 
                     if (!rectToClipOut.isEmpty()) {
                         context->clipOut(rectToClipOut);
                     }
                 }
             }
 
             // Draw only the shadow.
-            DrawLooper drawLooper;
-            drawLooper.addShadow(shadowOffset, shadowBlur, shadowColor,
+            RefPtr<DrawLooper> drawLooper = adoptRef(new DrawLooper);
+            drawLooper->addShadow(shadowOffset, shadowBlur, shadowColor,
                 DrawLooper::ShadowRespectsTransforms, DrawLooper::ShadowIgnoresAlpha);
-            context->setDrawLooper(drawLooper);
+            context->setDrawLooper(drawLooper.release());
 
             if (hasBorderRadius) {
                 RoundedRect influenceRect(shadowRect, border.radii());
                 influenceRect.expandRadii(2 * shadowBlur + shadowSpread);
                 if (allCornersClippedOut(influenceRect, info.rect))
                     context->fillRect(fillRect.rect(), Color::black);
                 else {
                     fillRect.expandRadii(shadowSpread);
                     if (!fillRect.isRenderable())
                         fillRect.adjustRadii();
@@ skipping 256 matching lines @@
     ASSERT(!beforeChild || toBoxModelObject == beforeChild->parent());
     for (RenderObject* child = startChild; child && child != endChild; ) {
         // Save our next sibling as moveChildTo will clear it.
         RenderObject* nextSibling = child->nextSibling();
         moveChildTo(toBoxModelObject, child, beforeChild, fullRemoveInsert);
         child = nextSibling;
     }
 }
 
 } // namespace WebCore