Git commits in Moodle 3.3.x by Ruslan Kabalin

commit fc9bc65863735ae1cb3ef023625e7f8e53144209
Author: Ruslan Kabalin <r.kabalin@lancaster.ac.uk>
Date:   Fri, 07 Apr 2017 18:57:35 +0800
Tag:    v3.3.0-beta

MDL-58539 assignfeedback_editpdf: Fix group assignment fatal error.