constructor() {

    /** @export {string} */
    this.layerId;
    /** @export {number} */
    this.zoomLevel;
    /** @export {number} */
    this.throttleCount;
    /** @export {number} */
    this.errorCount;
    /** @export {!Array<number>} */
    this.tileLatencies;
  }
Data structure containing statistics for an AbstractOverlay
@record @struct