Oilpan: have xml/ objects on the heap by default.

Source/core/xml/XPathNodeSet.cpp

 /*
  * Copyright (C) 2007 Alexey Proskuryakov <ap@webkit.org>
  *
  * 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 23 matching lines @@
 namespace blink {
 namespace XPath {
 
 // When a node set is large, sorting it by traversing the whole document is
 // better (we can assume that we aren't dealing with documents that we cannot
 // even traverse in reasonable time).
 const unsigned traversalSortCutoff = 10000;
 
 typedef WillBeHeapVector<RawPtrWillBeMember<Node>> NodeSetVector;
 
-PassOwnPtrWillBeRawPtr<NodeSet> NodeSet::create(const NodeSet& other)
+NodeSet* NodeSet::create(const NodeSet& other)
 {
-    OwnPtrWillBeRawPtr<NodeSet> nodeSet = NodeSet::create();
+    NodeSet* nodeSet = NodeSet::create();
     nodeSet->m_isSorted = other.m_isSorted;
     nodeSet->m_subtreesAreDisjoint = other.m_subtreesAreDisjoint;
     nodeSet->m_nodes.appendVector(other.m_nodes);
-    return nodeSet.release();
+    return nodeSet;
 }
 
 static inline Node* parentWithDepth(unsigned depth, const NodeSetVector& parents)
 {
     ASSERT(parents.size() >= depth + 1);
     return parents[parents.size() - 1 - depth];
 }
 
 static void sortBlock(unsigned from, unsigned to, WillBeHeapVector<NodeSetVector>& parentMatrix, bool mayContainAttributeNodes)
 {
@@ skipping 213 matching lines @@
 Node* NodeSet::anyNode() const
 {
     if (isEmpty())
         return 0;
 
     return m_nodes.at(0).get();
 }
 
 }
 }