Git merges in Moodle 3.5.2 by Víctor Déniz Falcón

commit f1019f4616aee4c9e699ac82bb0d283c20d2a63e
Author: Víctor Déniz Falcón <victor@moodle.com>
Date:   Mon, 03 Sep 2018 13:56:27 +0800
Tag:    v3.5.2

Merge branch 'MDL-63255-35' of git://github.com/vmdef/moodle into MDL-63255-35-test