src/vs/workbench/api/browser/mainThreadQuickOpen.ts/MainThreadQuickOpen/$setError
class MainThreadQuickOpen:	$setError(instance: number, error: Error): Promise<void> {
		if (this._items[instance]) {
			this._items[instance].reject(error);
			delete this._items[instance];
		}
		return Promise.resolve();
	}