Author: Stephen Bourget
MDL-55566 chat: Improve next scheduled chat message
http://git.moodle.org/gw?p=moodle.git;a=commit;h=3bf46ee7172d3cacf103dd0f7997f83c452d286b
http://github.com/moodle/moodle/commit/3bf46ee7172d3cacf103dd0f7997f83c452d286b
+ 3.2 en [sessionstart,mod_chat]