PLAT-6832/6829

- credit missing data field
- in-memory snapshot master  getNamedSnapshot rather than getSnapshot
The issue is that this change will cause compilation errors on currently working code. I agree that invalid states should be corrected but the way to do that is to deprecate the current constructors and change their implementations to something more valid or else throw an UnsupportedOperationException. These new constructors should then be added and referenced from the old ones.