Git commits in Moodle 3.4.3 by Eric Merrill

commit f539686553372f7c390110668642f8bf66173f2b
Author: Eric Merrill <merrill@oakland.edu>
Date:   Tue, 10 Apr 2018 02:47:50 +0800
Tag:    v3.4.3

MDL-61913 restore: Protect against blocks that aren't being created