return *kNullStr;
static nsCString sNullStr; return sNullStr;
SearchKeywordTable(PRInt32 aValue, const PRInt32 aTable[]){  PRInt32 i = SearchKeywordTableInt(aValue, aTable);  if (i < 0) {    return *kNullStr;  } else {    return nsCSSKeywords::GetStringValue(nsCSSKeyword(i));  }}