TIMESTAMPADD() and TIMESTAMPDIFF() returned syntax error when FRAC_SECOND is used

Build tested:

getcalpontsoftwareinfo Mon May 23 15:52:13 2016

Name : infinidb-platform Relocations: (not relocatable)
Version : 5.0 Vendor: MariaDB, Inc.
Release : 0 Build Date: Sun 15 May 2016 07:24:29 PM CDT
Install Date: Mon 16 May 2016 05:21:51 PM CDT Build Host: srvbuilder

The issue was identified by Autopilot's functions test:

MariaDB [mytest]> select cidx, CDATE, TIMESTAMPADD(FRAC_SECOND,5,CDATE) from datatypetestm order by cidx;
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'FRAC_SECOND,5,CDATE) from datatypetestm order by cidx' at line 1
MariaDB [mytest]> select cidx, CDATETIME, TIMESTAMPADD(FRAC_SECOND,5,CDATETIME) from datatypetestm order by cidx;
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'FRAC_SECOND,5,CDATETIME) from datatypetestm order by cidx' at line 1
MariaDB [mytest]> select cidx, CDATE, TIMESTAMPDIFF(FRAC_SECOND,CDATE, '2011-05-06 11:09:36') from datatypetestm order by cidx;
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'FRAC_SECOND,CDATE, '2011-05-06 11:09:36') from datatypetestm order by cidx' at line 1
MariaDB [mytest]> select cidx, CDATETIME, TIMESTAMPDIFF(FRAC_SECOND,CDATETIME, '2011-05-06 11:09:36') from datatypetestm order by cidx;
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'FRAC_SECOND,CDATETIME, '2011-05-06 11:09:36') from datatypetestm order by cidx' at line 1