Prior to SERVER-74611 it wasn't clear whether WaitForMajorityService was waiting for write concern majority (wait for an optime to be made durable on the current primary and a majority of the set, assert on stepdown) or read concern majority (wait for an optime to make it into the majority committed snapshot, regardless of stepdowns). It was in fact write concern majority. SERVER-74611 adds a call to do the same for read concern majority called waitForMajorityForRead. This ticket is to replace old uses of waitForMajority with the new (identical) call waitForMajorityForWrite and remove waitForMajority.