Problem : Code responsible for reading/writing from/to acl tables
          assume that storage engine is always MYISAM. Hence, some
          errors reported by different storage engines (e.g. ndb)
          are not processed correctly.

Solution : Handle errors thrown by storage engine and bail out if
           error is not acceptable. This change also signals
           transaction rollback to storage engine in case of an
           unexpected error by storage engine.

Reviewed-By: Georgi Kodinov <georgi.kodinov@oracle.com>
Reviewed-By: Dmitry Lenev <dmitry.lenev@oracle.com>
Reviewed-By: Magnus Blåudd <magnus.blaudd@oracle.com>