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

Source/core/dom/TreeScope.cpp

 /*
  * Copyright (C) 2011 Google Inc. All Rights Reserved.
  * Copyright (C) 2012 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 152 matching lines @@
 {
     if (!m_elementsById)
         return;
     m_elementsById->remove(elementId.impl(), element);
     m_idTargetObserverRegistry->notifyObservers(elementId);
 }
 
 Node* TreeScope::ancestorInThisScope(Node* node) const
 {
     while (node) {
-        if (&node->treeScope() == this)
+        if (node->treeScope() == this)
             return node;
         if (!node->isInShadowTree())
             return 0;
 
         node = node->shadowHost();
     }
 
     return 0;
 }
 
@@ skipping 188 matching lines @@
             return toElement(targetStack.last());
         }
         if (node->isShadowRoot()) {
             ASSERT(!targetStack.isEmpty());
             targetStack.removeLast();
         }
     }
     return 0;
 }
 
-unsigned short TreeScope::comparePosition(const TreeScope& otherScope) const
+unsigned short TreeScope::comparePosition(NonNullPtr<const TreeScope> otherScope) const
 {
-    if (&otherScope == this)
+    if (otherScope == this)
         return Node::DOCUMENT_POSITION_EQUIVALENT;
 
     Vector<const TreeScope*, 16> chain1;
     Vector<const TreeScope*, 16> chain2;
     const TreeScope* current;
     for (current = this; current; current = current->parentTreeScope())
         chain1.append(current);
-    for (current = &otherScope; current; current = current->parentTreeScope())
+    for (current = otherScope.get(); current; current = current->parentTreeScope())
         chain2.append(current);
 
     unsigned index1 = chain1.size();
     unsigned index2 = chain2.size();
     if (chain1[index1 - 1] != chain2[index2 - 1])
         return Node::DOCUMENT_POSITION_DISCONNECTED | Node::DOCUMENT_POSITION_IMPLEMENTATION_SPECIFIC;
 
     for (unsigned i = std::min(index1, index2); i; --i) {
         const TreeScope* child1 = chain1[--index1];
         const TreeScope* child2 = chain2[--index2];
@@ skipping 14 matching lines @@
     // There was no difference between the two parent chains, i.e., one was a subset of the other. The shorter
     // chain is the ancestor.
     return index1 < index2 ?
         Node::DOCUMENT_POSITION_FOLLOWING | Node::DOCUMENT_POSITION_CONTAINED_BY :
         Node::DOCUMENT_POSITION_PRECEDING | Node::DOCUMENT_POSITION_CONTAINS;
 }
 
 static void listTreeScopes(Node* node, Vector<TreeScope*, 5>& treeScopes)
 {
     while (true) {
-        treeScopes.append(&node->treeScope());
+        treeScopes.append(node->treeScope().get());
         Element* ancestor = node->shadowHost();
         if (!ancestor)
             break;
         node = ancestor;
     }
 }
 
 TreeScope* commonTreeScope(Node* nodeA, Node* nodeB)
 {
     if (!nodeA || !nodeB)
         return 0;
 
-    if (&nodeA->treeScope() == &nodeB->treeScope())
-        return &nodeA->treeScope();
+    if (nodeA->treeScope() == nodeB->treeScope())
+        return nodeA->treeScope().get();
 
     Vector<TreeScope*, 5> treeScopesA;
     listTreeScopes(nodeA, treeScopesA);
 
     Vector<TreeScope*, 5> treeScopesB;
     listTreeScopes(nodeB, treeScopesB);
 
     size_t indexA = treeScopesA.size();
     size_t indexB = treeScopesB.size();
 
@@ skipping 15 matching lines @@
 }
 #endif
 
 int TreeScope::refCount() const
 {
     if (Node* root = rootNode())
         return root->refCount();
     return 0;
 }
 
-bool TreeScope::isInclusiveAncestorOf(const TreeScope& scope) const
+bool TreeScope::isInclusiveAncestorOf(NonNullPtr<const TreeScope> scope) const
 {
-    for (const TreeScope* current = &scope; current; current = current->parentTreeScope()) {
+    for (const TreeScope* current = scope.get(); current; current = current->parentTreeScope()) {
         if (current == this)
             return true;
     }
     return false;
 }
 
 Element* TreeScope::getElementByAccessKey(const String& key) const
 {
     if (key.isEmpty())
         return 0;
     Element* result = 0;
     Node* root = rootNode();
     for (Element* element = ElementTraversal::firstWithin(root); element; element = ElementTraversal::next(element, root)) {
         if (element->fastGetAttribute(accesskeyAttr) == key)
             result = element;
         for (ShadowRoot* shadowRoot = element->youngestShadowRoot(); shadowRoot; shadowRoot = shadowRoot->olderShadowRoot()) {
             if (Element* shadowResult = shadowRoot->getElementByAccessKey(key))
                 result = shadowResult;
         }
     }
     return result;
 }
 
 } // namespace WebCore