local echo (4/n): Migrate more fields to PerAccountStoreBase

[PIG208]

MessageStore will need to access queueId and selfUserId later for outbox message support.

[gnprice]

I see we were thinking in a similar direction today 🙂. I just sent #1467 which does the selfUserId portion of this (including some changes borrowed from this PR), as well as a number of other fields. How about you rebase the queueId commit atop that?

[PIG208]

Thanks! This has been rebased atop #1467.

[chrisbobbe]

#1467 has been merged, and GitHub says there are some conflicts; could you rebase again?

[chrisbobbe]

Thanks! Small comment below.

[chrisbobbe]

Is it intentional to move this from the section

  ////////////////////////////////
  // Where data comes from in the first place.

to the section

  ////////////////////////////////
  // Data attached to the self-account on the realm.

?

[PIG208]

I want to position this after connection and before accountId, and I feel that it fits a bit better as it is associated with the self-account. But keeping it in the original section works too (proximity to UpdateMachine, queueId's old home, was a reason why it was there).

[chrisbobbe]

Thanks for explaining; otherwise it looks like an accident 🙂 perhaps Greg has thoughts about it.

[gnprice]

Yeah, I think up next to connection in the "Where data comes from in the first place" section would be better.

I see the queue ID as much more like the connection than it is like the account. It's part of "where data comes from" — each getEvents call passes it in order to get the right events.

Conversely it's not really "attached to" the self-account, in that there may be zero, one, or many queues at any given time for a given account and the queues are fairly ephemeral.

[PIG208]

Makes sense. Move it up to be right after connection.

[gnprice]

Thanks, and thanks @chrisbobbe for the review!

LGTM modulo the thread above.