Remove RenderWidget.

sky/engine/core/rendering/RenderObject.h

 /*
  * 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, 2012 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 492 matching lines @@
     Node* node() const
     {
         return isAnonymous() ? 0 : m_node.get();
     }
 
     Node* nonPseudoNode() const
     {
         return node();
     }
 
-    // FIXME: Why does RenderWidget need this?
-    void clearNode() { m_node = nullptr; }
-
     // FIXME(sky): remove this.
     Node* generatingNode() const { return node(); }
 
     Document& document() const { return m_node->document(); }
     LocalFrame* frame() const { return document().frame(); }
 
     // Returns the object containing this one. Can be different from parent for positioned elements.
     // If paintInvalidationContainer and paintInvalidationContainerSkipped are not null, on return *paintInvalidationContainerSkipped
     // is true if the renderer returned is an ancestor of paintInvalidationContainer.
     RenderObject* container(const RenderLayerModelObject* paintInvalidationContainer = 0, bool* paintInvalidationContainerSkipped = 0) const;
@@ skipping 817 matching lines @@
 void showTree(const blink::RenderObject*);
 void showLineTree(const blink::RenderObject*);
 void showRenderTree(const blink::RenderObject* object1);
 // We don't make object2 an optional parameter so that showRenderTree
 // can be called from gdb easily.
 void showRenderTree(const blink::RenderObject* object1, const blink::RenderObject* object2);
 
 #endif
 
 #endif // RenderObject_h