Deleted documents can be browsed and previewed by non-admins

Step to reproduce :

• Create a private space in your wiki. Private means the space should be visible to nobody but you.
• Create documents in this space.
• Delete the space.
• Then the space (and all its documents) is in the bin, but since you deleted it, rights are also removed.
• 2 issues here : the bin is public and anyone can access those documents.

In my opinion, we should not let anyone but admins reach the bin and the documents inside too.