val->SetString(list->mListStyleImage);
nsCOMPtr<nsIURI> uri; if (list->mListStyleImage) { list->mListStyleImage->GetURI(getter_AddRefs(uri)); } val->SetURI(uri);
nsComputedDOMStyle::GetListStyleImage(nsIFrame *aFrame,                                      nsIDOMCSSPrimitiveValue*& aValue){  nsROCSSPrimitiveValue* val=GetROCSSPrimitiveValue();  NS_ENSURE_TRUE(val, NS_ERROR_OUT_OF_MEMORY);  const nsStyleList* list;  GetStyleData(eStyleStruct_List, (const nsStyleStruct*&)list, aFrame);  if(list) {    if (list->mListStyleImage.IsEmpty()) {      val->SetString(NS_LITERAL_STRING("none"));    } else {      val->SetString(list->mListStyleImage);    }  }  else {    val->SetString(NS_LITERAL_STRING("none"));  }      return val->QueryInterface(NS_GET_IID(nsIDOMCSSPrimitiveValue),                             (void**)&aValue);}