Have NodeChildRemovalTracker constructor take a reference

Source/core/dom/NodeChildRemovalTracker.h

 /*
  * Copyright (C) 2013 Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Neither the name of Google Inc. nor the names of its
@@ skipping 15 matching lines @@
 
 #ifndef NodeChildRemovalTracker_h
 #define NodeChildRemovalTracker_h
 
 #include "core/dom/Node.h"
 
 namespace WebCore {
 
 class NodeChildRemovalTracker {
 public:
-    explicit NodeChildRemovalTracker(Node*);
+    explicit NodeChildRemovalTracker(Node&);
     ~NodeChildRemovalTracker();
 
     static bool isBeingRemoved(Node*);
 
 private:
-    Node* node() const { return m_node; }
+    Node& node() const { return m_node; }
     NodeChildRemovalTracker* previous() { return m_previous; }
 
-    Node* m_node;
+    Node& m_node;
     NodeChildRemovalTracker* m_previous;
     static NodeChildRemovalTracker* s_last;
 };
 
-inline NodeChildRemovalTracker::NodeChildRemovalTracker(Node* node)
+inline NodeChildRemovalTracker::NodeChildRemovalTracker(Node& node)
     : m_node(node)
     , m_previous(s_last)
 {
     s_last = this;
 }
 
 inline NodeChildRemovalTracker::~NodeChildRemovalTracker()
 {
     s_last = m_previous;
 }
 
 inline bool NodeChildRemovalTracker::isBeingRemoved(Node* node)
 {
     for (NodeChildRemovalTracker* removal = s_last; removal; removal = removal->previous()) {
-        if (removal->node()->containsIncludingShadowDOM(node))
+        if (removal->node().containsIncludingShadowDOM(node))
             return true;
     }
 
     return false;
 }
 
 } // namespace
 
 #endif