src/vs/workbench/browser/parts/notifications/notificationsStatus.ts/NotificationsStatus/onDidChangeNotification
class NotificationsStatus:	private onDidChangeNotification(e: INotificationChangeEvent): void {

		// Consider a notification as unread as long as it only
		// appeared as toast and not in the notification center
		if (!this.isNotificationsCenterVisible) {
			if (e.kind === NotificationChangeType.ADD) {
				this.newNotificationsCount++;
			} else if (e.kind === NotificationChangeType.REMOVE && this.newNotificationsCount > 0) {
				this.newNotificationsCount--;
			}
		}

		// Update in status bar
		this.updateNotificationsCenterStatusItem();
	}