Author: adrian@moodle.com
MDL-20627 user - Fixed viewing permission of email when sending group messages.
http://git.moodle.org/gw?p=moodle.git;a=commit;h=e94113a859015a4a80b9397957b8fc4044e2951f
http://github.com/moodle/moodle/commit/e94113a859015a4a80b9397957b8fc4044e2951f
+ 2.2 en [emaildisplayhidden,core]