[validation] False positive: unreachable code

[Lynorics]

The following code gives a false positive for the first if-statement, telling "unreachable code"

  internal static function curtail(s:String):String {
    if (!s) return '';
    if (s.length > SHORT_NAME_MAX_LENGTH) {
      return s.substr(0, SHORT_NAME_MAX_LENGTH - 3) + '...';
    }
    return s;
  }