Author: Zig Tan
MDL-61881 report_courseoverview: Implement null privacy provider
http://git.moodle.org/gw?p=moodle.git;a=commit;h=16044f514005fca06cbfe8b30b9fa39b5f70cbff
http://github.com/moodle/moodle/commit/16044f514005fca06cbfe8b30b9fa39b5f70cbff
+ 3.5 en [privacy:metadata,report_courseoverview]