Summary:
This diff adds an "OutboxStore" which reflects the TaskQueue and
adds a progress bar / cancel button to drafts which are currently sending.
- Sending state is different from things like Send later because drafts
which are sending shouldn't be editable. You should have to stop them
from sending before editing. I think we can implement "Send Later"
indicators, etc. with a simple InjectedComponentSet on the draft list
rows, but the OutboxStore is woven into the DraftList query subscription
so every draft has a `uploadTaskId`.
- The TaskQueue now saves periodically (every one second) when there are
"Processing" tasks. This is not really necessary, but makes it super
easy for tasks to expose "progress", because they're essentially
serialized and propagated to all windows every one second with the
current progress value. Kind of questionable, but super convenient.
- I also cleaned up ListTabular and MultiselectList a bit because they
applied the className prop to an inner element and not the top one.
- If a DestroyDraft task is created for a draft without a server id, it
ends with Task.Status.Continue and not Failed.
- The SendDraftTask doesn't delete uploads until the send actually goes
through, in case the app crashes and it forgets the file IDs it created.
Test Plan: Tests coming soon
Reviewers: juan, evan
Reviewed By: evan
Differential Revision: https://phab.nylas.com/D2524
