constructor(tileCoord, state, src, extent, preemptive, jsonp) {
    super(tileCoord, state);

    /**
     * @private
     * @type {string}
     */
    this.src_ = src;

    /**
     * @private
     * @type {import("../extent.js").Extent}
     */
    this.extent_ = extent;

    /**
     * @private
     * @type {boolean}
     */
    this.preemptive_ = preemptive;

    /**
     * @private
     * @type {Array<string>}
     */
    this.grid_ = null;

    /**
     * @private
     * @type {Array<string>}
     */
    this.keys_ = null;

    /**
     * @private
     * @type {Object<string, Object>|undefined}
     */
    this.data_ = null;

    /**
     * @private
     * @type {boolean}
     */
    this.jsonp_ = jsonp;
  }
@param {import("../tilecoord.js").TileCoord} tileCoord Tile coordinate.
@param {import("../TileState.js").default} state State.
@param {string} src Image source URI.
@param {import("../extent.js").Extent} extent Extent of the tile.
@param {boolean} preemptive Load the tile when visible (before it's needed).
@param {boolean} jsonp Load the tile as a script.