The flag must be separate so as to not contaminate the user's savegame.
Fixes the following use cases that were broken before:
- Content file edits a reference that was already deleted by a previously loaded content file -> reference must stay deleted
- Changed or new content file deletes a reference that is already present in the user's savegame -> reference must be deleted
- Said content file is disabled again - reference must be undeleted
It was just adding a level of indirection to Ptr.getClass().
All the call were replaced by that instead. The number of lines changed
is important, but the change itself is trivial, so everything should be
fine. :)