Assign one new user the Map Author role caused deletion of Administrator role

[brucedechant]

When a new usr is assigned the Map Author role it causes the deletion of the Administrator role. This in turn causes the Administrator to no longer have access to the site.

Steps to reproduce this defect:

1. Launch MG site administrator. 
2. Create a new user.
3. Assign the user the Map Author role.

Results: Error occurs - Administrator role cannot access the Site anymore.

Expected results: After assigning the role, each user still works as usual.