This patch fixes 2 problems with MariaDB backup:
1) If a user with grants to a database has a hyphenated name, the backup
script errors out and the grants for this user won't be saved in the backup.
2) While restoring databases from a backup, if connections are allowed
during the restore operation, there is potential for deadlock. Table
level locks are added to the backup sql file in order to try to prevent
these deadlock situations.
Change-Id: If612e7b9f3f4d75fc67018eea17609f07a0c0b0f
41342cdc4a