Git commits in Moodle 3.6.4 by Alexander Bias

commit 07c0e0e0906d6c94cc7549e67fd6f37847a1a601
Author: Alexander Bias <alexander.bias@uni-ulm.de>
Date:   Wed, 01 May 2019 03:33:52 +0800
Tag:    v3.6.4

MDL-65157 core_completion: no progress for untracked users