e `<paper-ripple>` element used by this element to create
     * ripple effects. The element's ripple is created on demand, when
     * necessary, and calling this method will force the
     * ripple to be created.
     */
    getRipple: function() {
      this.ensureRipple();
      return this._ripple;
    },

    /**
     * Returns true if this element currently contains a ripple effect.
     * @return {boolean}
     */
    hasRipple: function() {
      return Boolean(this._ripple);
    },

    /**
     *