rv = NS_NewISupportsArray(getter_AddRefs(mStyleSheets));
rv = NS_NewISupportsArray(getter_AddRefs(mStyleSheetReferences));
nsXULPrototypeDocument::Init(){    nsresult rv;    rv = NS_NewISupportsArray(getter_AddRefs(mStyleSheets));    if (NS_FAILED(rv)) return rv;    rv = NS_NewISupportsArray(getter_AddRefs(mOverlayReferences));    if (NS_FAILED(rv)) return rv;    return NS_OK;}