return this.substituteString.apply(this, args);
        }

        /**
   * Make a string safe for use with with Polymer bindings that are
   * inner-h-t-m-l (or other innerHTML use).
   * @param {string} rawString The unsanitized string.
   * @param {SanitizeInnerHtmlOpts=} opts Optional additional allowed tags and
   *     attributes.
   * @return {string}
   */
        sanitizeInnerHtml(rawString, opts) {
            opts = opts || {};
            return parseHtmlSubset('<b>' + rawString + '</b>', opts.t