setUrl(url) {
    assert(this.format_, '`format` must be set when `url` is set');
    this.url_ = url;
    this.setLoader(xhr(url, this.format_));
  }
Points the source to a new url. The next render cycle will use the new url.
@param {string|import("../featureloader.js").FeatureUrlFunction} url Url.
@api