Git commits in Moodle 3.7.5 by David Balch

commit b74030550e8206f233f4bfccb7ea1b56af5e6550
Author: David Balch <david.balch@conted.ox.ac.uk>
Date:   Tue, 18 Feb 2020 20:24:05 +0800
Tag:    v3.7.5

MDL-67993 roles: Fix pix_icon() calls.