Reduce repetitive EventTarget subclassing

Source/core/dom/Node.cpp

Index: Source/core/dom/Node.cpp
diff --git a/Source/core/dom/Node.cpp b/Source/core/dom/Node.cpp
index 89a1bc4bef41755f219b6a59a7d310da52cbb722..4551b65782c60d52aa0a66ad27c190c6100b2f63 100644
--- a/Source/core/dom/Node.cpp
+++ b/Source/core/dom/Node.cpp
@@ -2104,14 +2104,14 @@ EventTargetData* Node::eventTargetData()
     return hasEventTargetData() ? eventTargetDataMap().get(this) : 0;
 }
 
-EventTargetData* Node::ensureEventTargetData()
+EventTargetData& Node::ensureEventTargetData()
 {
     if (hasEventTargetData())
-        return eventTargetDataMap().get(this);
+        return *eventTargetDataMap().get(this);
     setHasEventTargetData(true);
     EventTargetData* data = new EventTargetData;
     eventTargetDataMap().set(this, adoptPtr(data));
-    return data;
+    return *data;
 }
 
 void Node::clearEventTargetData()