Troubleshoot Bad Request 400 "User would be locked out of page with given grants and restrictions"

If you create a role other than the default roles and you give that role CHANGEPERMISSIONS, then when that role tries to restrict a page as Private or Semi Public, the system will return the following error:  "Bad Request 400 - User would be locked out of page with given grants and restrictions".  This is tied to a permissions flag in the database that can be changed by running the following MySQL queries:

update restrictions set restriction_perm_flags = 1039 where restriction_name = 'Semi-Public';

update restrictions set restriction_perm_flags = 1025 where restriction_name = 'Private';

This will then make sure that when a user that has a role other than the default role, will be able to apply permissions without the error message. More detailed explanation of the problem here