Git merges in Moodle 3.6.9 by Andrew Nicols

commit 8e6ccd11b130329d9594126100144d3890f151d0
Author: Andrew Nicols <andrew@nicols.co.uk>
Date:   Thu, 06 Feb 2020 10:22:07 +0800
Tag:    v3.6.9

Merge branch 'MDL-67175-36' of git://github.com/ferranrecio/moodle into MOODLE_36_STABLE