Ownership IDs not being transferred in custom reports

[melvyng]

If an user (eg. user A) has created some custom reports using the "Report builder", the owner id is stored in the field "usercreated" and "usermodified" in the table "mdl_reportbuilder_report". When merging accounts, from user A to user B, the ownership ID is not being transfered in the table "mdl_reportbuilder_report" to the user B, so the user B can't see the previous reports created by user A.