This diff does two things:
- Resolves ENG-9055 by bringing back ADD_MEMBERS permissions. Unfortunately we have no way to determine which communities had this permission before the errant migration, so I'm just assuming they all had it (as it's a default) and bringing it back for all communities.
- Recalculates all permissions so that the changes in the last two diffs in the stack are applied.
Depends on D13113