         // true
     * Polymer.Path.isAncestor('foo.bar', 'foo.bar')     // false
     * Polymer.Path.isAncestor('foo.bar', 'foo.bar.baz') // false
     * ```
     *
     * @memberof Polymer.Path
     * @param {string} base Path string to test against.
     * @param {string} path Path string to test.
     * @return {boolean} True if `path` is an ancestor of `base`.
     */
    isAncestor: function(base, path) {
      //     base.startsWith(path + '.');
      return base.indexOf(path + '.') === 0;
    },

 