The TopbarSweeper cache clearing system only ever acts on User.current. This means if an admin toggles the admin flag on another user/group, that user's topbar does not refresh and show updated entries until the cache naturally times out (or is cleared with =foreman-rake tmp:cache:clear=).

Steps to reproduce:
1. Create a user without admin flag or roles
2. In a separate browser sesson, log in with that user.
  => observe they can only see Hosts and Bookmarks
3. Create a user group, give it the admin flag, and assign the above user to it
4. Refresh the user's page

Expected results:
The user can now see all menu entries on the topbar

Actual result:
The user still only sees Hosts and Bookmarks