method in ZCF for contracts to know their upgrade state

[turadg]

What is the Problem Being Solved?

It’s a little error prone that contracts have to look in their baggage for a thing to know whether they’re upgrading.

Description of the Design

Some method on the ZCF that a contract start fn can call to learn which incarnation it's in. Maybe initial or upgrading, or some incarnation number.

It would have to be threaded through from Zoe. Neither is currently tracking that state. In order to get a definitive answer rather than an ad hoc indication, Zoe would want to get an answer from Swingset, so needs needs-design.

Security Considerations

Scaling Considerations

Test Plan

Upgrade Considerations