function getConstructorName(Constructor) {
    switch (Constructor) {
        case Intl.Collator:
            return "Collator";
        case Intl.NumberFormat:
            return "NumberFormat";
        case Intl.DateTimeFormat:
            return "DateTimeFormat";
        default:
            $ERROR("test internal error: unknown Constructor");
    }
}
Returns the name of the given constructor object, which must be one of
Intl.Collator, Intl.NumberFormat, or Intl.DateTimeFormat.
@param {object} Constructor a constructor
@return {string} the name of the constructor