src/vs/workbench/services/notification/common/notificationService.ts/NotificationService/registerListeners
class NotificationService:	private registerListeners(): void {
		this._register(this.model.onDidChangeNotification(e => {
			switch (e.kind) {
				case NotificationChangeType.ADD:
				case NotificationChangeType.REMOVE: {
					const notification: INotification = {
						message: e.item.message.original,
						severity: e.item.severity,
						source: typeof e.item.sourceId === 'string' && typeof e.item.source === 'string' ? { id: e.item.sourceId, label: e.item.source } : e.item.source,
						silent: e.item.silent
					};

					if (e.kind === NotificationChangeType.ADD) {
						this._onDidAddNotification.fire(notification);
					}

					if (e.kind === NotificationChangeType.REMOVE) {
						this._onDidRemoveNotification.fire(notification);
					}

					break;
				}
			}
		}));
	}