nsXTFXULDisplayFrame* it = new (aPresShell) nsXTFXULDisplayFrame(aPresShell); if (nsnull == it) return NS_ERROR_OUT_OF_MEMORY;  *aNewFrame = it;  return NS_OK;
return new (aPresShell) nsXTFXULDisplayFrame(aPresShell);
NS_NewXTFXULDisplayFrame(nsIPresShell* aPresShell, nsIFrame** aNewFrame){  nsXTFXULDisplayFrame* it = new (aPresShell) nsXTFXULDisplayFrame(aPresShell);  if (nsnull == it)    return NS_ERROR_OUT_OF_MEMORY;  *aNewFrame = it;  return NS_OK;}