Git commits in Moodle 2.7.5 by Russell Smith

commit b2fb93f89b2045fc17a392bac02bd5787f6480bd
Author: Russell Smith <mr-russ@smith2001.net>
Date:   Thu, 12 Dec 2013 00:33:20 +0800
Tag:    v2.7.5

MDL-43421 logging: Ignore race condition in access update.