NS_ENSURE_ARG_POINTER(aResult);
NS_PRECONDITION(aResult, "Null out ptr");
NS_NewHTMLFragmentContentSink2(nsIHTMLFragmentContentSink** aResult){  NS_ENSURE_ARG_POINTER(aResult);  nsCOMPtr<nsHTMLFragmentContentSink2> it;  NS_NEWXPCOM(it, nsHTMLFragmentContentSink2);  NS_ENSURE_TRUE(it, NS_ERROR_OUT_OF_MEMORY);