function isWhitespace(charCode) {
    return ((charCode <= 160 && (charCode >= 9 && charCode <= 13) || charCode == 32 || charCode == 160) || charCode == 5760 || charCode == 6158 ||
      (charCode >= 8192 && (charCode <= 8202 || charCode == 8232 || charCode == 8233 || charCode == 8239 || charCode == 8287 || charCode == 12288 || charCode == 65279)));
  }
Used by `trimmedLeftIndex` and `trimmedRightIndex` to determine if a
character code is whitespace.

@private
@param {number} charCode The character code to inspect.
@returns {boolean} Returns `true` if `charCode` is whitespace, else `false`.