/**
 * Cancels an animation frame, a custom implementation of the native
 * `cancelAnimationFrame` function. If the browser has no native
 * `cancelAnimationFrame` function defined, this function will simulate its
 * behavior using a timeout.
 *
 * @param requestId The request ID as a result of `requestAnimationFrame` or
 *                  `setTimeout` (native `requestAnimationFrame` is unavailable)
 *                  of which the animation frame request is to be cancelled.
 */
export declare function cancelAnimationFrame(requestId: number): any;