Usage is not updated correctly when deleting node with reference

[Sebobo]

Got this feedback from a customer:

When deleting an item, the usages are displayed incorrectly for documents in Media Management.

Procedure:

1. Create new article
2. Insert new image
3. Insert new document in download area
4. Publish article
5. Check media management --> usage is displayed correctly - 1x in usage in new article
6. Delete article
7. Publish changes
8. article is deleted and not findable --> correct behavior
9. Control Media Management --> Usage is not displayed correctly - new says 2x in use and on control displays location with cryptic letter number sequence and "Private Workspace".