Author: Zig Tan
MDL-61568 repository_user: Implement null privacy provider
http://git.moodle.org/gw?p=moodle.git;a=commit;h=9df4cecb2763f6f3deaa0db668dc55b69ef93a60
http://github.com/moodle/moodle/commit/9df4cecb2763f6f3deaa0db668dc55b69ef93a60
+ 3.4 en [privacy:metadata,repository_user]