clone() {
    const len = this.endss_.length;
    const newEndss = new Array(len);
    for (let i = 0; i < len; ++i) {
      newEndss[i] = this.endss_[i].slice();
    }

    const multiPolygon = new MultiPolygon(
      this.flatCoordinates.slice(),
      this.layout,
      newEndss,
    );
    multiPolygon.applyProperties(this);

    return multiPolygon;
  }
Make a complete copy of the geometry.
@return {!MultiPolygon} Clone.
@api
@override