src/vs/base/common/event.ts/accumulate
	export function accumulate<T>(event: Event<T>, delay: number = 0, disposable?: DisposableStore): Event<T[]> {
		return Event.debounce<T, T[]>(event, (last, e) => {
			if (!last) {
				return [e];
			}
			last.push(e);
			return last;
		}, delay, undefined, undefined, disposable);
	}