Author: Andrew Nicols
MDL-67913 core_table: Add filter classes
http://git.moodle.org/gw?p=moodle.git;a=commit;h=44effcb419cbeb02fbe3d90371eade3018382c83
http://github.com/moodle/moodle/commit/44effcb419cbeb02fbe3d90371eade3018382c83
+ 3.9 en [missingrequiredfields,core_table]