src/vs/base/common/async.ts/Limiter/constructor
class Limiter:	constructor(maxDegreeOfParalellism: number) {
		this.maxDegreeOfParalellism = maxDegreeOfParalellism;
		this.outstandingPromises = [];
		this.runningPromises = 0;
		this._onFinished = new Emitter<void>();
	}