[SB][Screen chips] Move `ongoingCallNotification` flow to background.

     * [CallType.Ongoing].

     */

    val ongoingCallNotification: Flow<ActiveNotificationModel?> =

        allRepresentativeNotifications.map { notifMap ->

            // Once a call has started, its `whenTime` should stay the same, so we can use it as a

            // stable sort value.

            notifMap.values.filter { it.callType == CallType.Ongoing }.minByOrNull { it.whenTime }

        allRepresentativeNotifications

            .map { notifMap ->

                // Once a call has started, its `whenTime` should stay the same, so we can use it as

                // a stable sort value.

                notifMap.values

                    .filter { it.callType == CallType.Ongoing }

                    .minByOrNull { it.whenTime }

            }

            .flowOn(backgroundDispatcher)

    /** Are any notifications being actively presented in the notification stack? */

    val areAnyNotificationsPresent: Flow<Boolean> =