Author: Zig Tan
MDL-61881 report_stats: Implement null privacy provider
http://git.moodle.org/gw?p=moodle.git;a=commit;h=b398f0702a61efd3af3cbe0aae36fac6b54bf0b0
http://github.com/moodle/moodle/commit/b398f0702a61efd3af3cbe0aae36fac6b54bf0b0
+ 3.5 en [privacy:metadata,report_stats]