Comment 9 for bug 1329772

Can confirm that I cannot get mysql_upgrade --upgrade-system-tables to fix the issue on CentOS 6.5:

[root@slave3 ~]# mysql_upgrade --upgrade-system-tables
Looking for 'mysql' as: mysql
The --upgrade-system-tables option was used, databases won't be touched.
This installation of MySQL is already upgraded to 5.6.17-66.0, use --force if you still need to run mysql_upgrade

[root@slave3 ~]# mysql_upgrade --force --upgrade-system-tables
Looking for 'mysql' as: mysql
The --upgrade-system-tables option was used, databases won't be touched.
Running 'mysql_fix_privilege_tables'...
Warning: Using a password on the command line interface can be insecure.
OK

[root@slave3 ~]# mysql
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 707024
Server version: 5.6.17-66.0-log Percona Server (GPL), Release 66.0, Revision 608

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Oracle is a registered trademark of Oracle Corporation and/or its
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Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> SELECT * FROM performance_schema.accounts;
ERROR 1682 (HY000): Native table 'performance_schema'.'accounts' has the wrong structure