mContent->ChildAt(PRInt32(mIndex), result);
mContent->ChildAt(PRInt32(mIndex), &result);
  already_AddRefed<nsIContent> get() const {    nsIContent* result = nsnull;    if (mNodes) {      nsCOMPtr<nsIDOMNode> node;      mNodes->Item(mIndex, getter_AddRefs(node));      CallQueryInterface(node, &result);    }    else       mContent->ChildAt(PRInt32(mIndex), result);    return result;  }