Author: Zig Tan
MDL-61881 report_performance: Implement null privacy provider
http://git.moodle.org/gw?p=moodle.git;a=commit;h=e95b8a7c7b5947ec54e1265ed25ae392de36b000
http://github.com/moodle/moodle/commit/e95b8a7c7b5947ec54e1265ed25ae392de36b000
+ 3.4 en [privacy:metadata,report_performance]