The rebuildIndexesOnCollection() function in the repair_database library still constructs the Collection class when rebuilding indexes in a collection here:

https://github.com/mongodb/mongo/blob/b4cb96852037aecfab27aa7b72a2ee586a3aa2e3/src/mongo/db/repair_database.cpp#L148

Delegating this construction call to one of the catalog interfaces such as DatabaseHolder will enable us to unshim the Collection class eventually.