Summary:
This diff fixes T3389 and makes it possible to define mail views which are not based on a category and focus them in the app.
I think that we need to create a new index on the starred attribute to make sure the query runs fast.
More tests WIP
Test Plan: Run tests, more coming soon!
Reviewers: dillon, evan
Reviewed By: evan
Maniphest Tasks: T3389
Differential Revision: https://phab.nylas.com/D1979
