src/vs/base/common/observableImpl/utils.ts/FromEventObservableSignal/handleEvent
class FromEventObservableSignal:	private readonly handleEvent = () => {
		transaction(
			(tx) => {
				for (const o of this.observers) {
					tx.updateObserver(o, this);
					o.handleChange(this, undefined);
				}
			},
			() => this.debugName
		);
	};