Story #3209: As a user, I have Repository Versions
Version incorrectly says that it removed a content unit
The squash code has a bug. Suppose you have 3 repo versions. Version 1 adds a unit, version 2 removes the unit, and version 3 re-adds the unit. If you remove version 2 then you have 2 RepositoryContent records pointing to version 3—one where version_removed is version 3 (but version_added is still version 1) and one where version_added is version 3. So the unit appears in 'removed' but is still in version 3's content.