WIP (Introduce WTF::NonNullPtr<T>.)

Source/core/dom/Node.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
  * 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
@@ skipping 21 matching lines @@
 #include "core/dom/SimulatedClickOptions.h"
 #include "core/dom/TreeScope.h"
 #include "core/editing/EditingBoundary.h"
 #include "core/inspector/InspectorCounters.h"
 #include "core/platform/TreeShared.h"
 #include "core/platform/graphics/LayoutRect.h"
 #include "core/rendering/style/RenderStyleConstants.h"
 #include "weborigin/KURLHash.h"
 #include "wtf/Forward.h"
 #include "wtf/ListHashSet.h"
+#include "wtf/NonNullPtr.h"
 #include "wtf/text/AtomicString.h"
 
 // This needs to be here because Document.h also depends on it.
 #define DUMP_NODE_STATISTICS 0
 
 namespace WebCore {
 
 class Attribute;
 class ClassNodeList;
 class ContainerNode;
@@ skipping 206 matching lines @@
     // class names (ex. class="foo bar") and other non-basic styling features. They and also control
     // if this element can participate in style sharing.
     //
     // FIXME: The only things that ever go through StyleResolver that aren't StyledElements are
     // PseudoElements and WebVTTElements. It's possible we can just eliminate all the checks
     // since those elements will never have class names, inline style, or other things that
     // this apparently guards against.
     bool isStyledElement() const { return isHTMLElement() || isSVGElement(); }
 
     bool isDocumentNode() const;
-    bool isTreeScope() const { return treeScope().rootNode() == this; }
+    bool isTreeScope() const { return treeScope()->rootNode() == this; }
     bool isDocumentFragment() const { return getFlag(IsDocumentFragmentFlag); }
     bool isShadowRoot() const { return isDocumentFragment() && isTreeScope(); }
     bool isInsertionPoint() const { return getFlag(IsInsertionPointFlag); }
 
     bool inNamedFlow() const { return getFlag(InNamedFlowFlag); }
     bool hasCustomStyleCallbacks() const { return getFlag(HasCustomStyleCallbacksFlag); }
 
     bool isRegisteredWithNamedFlow() const;
 
     bool hasSyntheticAttrChildNodes() const { return getFlag(HasSyntheticAttrChildNodesFlag); }
@@ skipping 194 matching lines @@
     Document* ownerDocument() const;
 
     // Returns the document associated with this node. A Document node returns itself.
     Document& document() const
     {
         ASSERT(this);
         ASSERT(documentInternal());
         return *documentInternal();
     }
 
-    TreeScope& treeScope() const { return *m_treeScope; }
+    NonNullPtr<TreeScope> treeScope() const { return m_treeScope; }
 
     // Returns true if this node is associated with a document and is in its associated document's
     // node tree, false otherwise.
     bool inDocument() const
     {
         ASSERT(documentInternal() || !getFlag(InDocumentFlag));
         return getFlag(InDocumentFlag);
     }
     bool isInShadowTree() const { return getFlag(IsInShadowTreeFlag); }
     bool isInTreeScope() const { return getFlag(static_cast<NodeFlags>(InDocumentFlag | IsInShadowTreeFlag)); }
@@ skipping 304 matching lines @@
     bool hasRareData() const { return getFlag(HasRareDataFlag); }
 
     NodeRareData* rareData() const;
     NodeRareData* ensureRareData();
     void clearRareData();
 
     void clearEventTargetData();
 
     void setHasCustomStyleCallbacks() { setFlag(true, HasCustomStyleCallbacksFlag); }
 
-    Document* documentInternal() const { return treeScope().documentScope(); }
+    Document* documentInternal() const { return treeScope()->documentScope(); }
     void setTreeScope(TreeScope* scope) { m_treeScope = scope; }
 
 private:
     friend class TreeShared<Node>;
 
     virtual PseudoId customPseudoId() const
     {
         ASSERT(hasCustomStyleCallbacks());
         return NOPSEUDO;
     }
@@ skipping 110 matching lines @@
 
 } //namespace
 
 #ifndef NDEBUG
 // Outside the WebCore namespace for ease of invocation from gdb.
 void showTree(const WebCore::Node*);
 void showNodePath(const WebCore::Node*);
 #endif
 
 #endif