private void removeMount(SlotReference slot) {
        mediaDetails.remove(slot);
        if (mediaMounts.remove(slot)) {
            deliverMountUpdate(slot, false);
        }
    }
private void removeMount ( SlotReference slot ) { mediaDetails . remove ( slot ) ; if ( mediaMounts . remove ( slot ) ) { deliverMountUpdate ( slot , false ) ; } }
Records that there is no media mounted in a particular media player slot, updating listeners if this is a change,
and clearing any affected items from our in-memory caches.

@param slot the slot in which no media is mounted