Summary:
There were several issues causing uploading to not work:
# The file upload response came back as a string instead of an Object. Needed to detect and `JSON.parse`
# The `MessageAttachment` component was not available as a package on the popout composer (since it used to be inside of `MessageList`)
# The `message.draft` bit was not set properly causing the DB changes to be ignored
# The actions notifying of `uploadStateChanged` were only being broadcasted in the main window (where the `TaskStore` is) and never making it to the popout composer.
Also keybindings for close window and up & down arrows were fixed.
Test Plan: edgehill --test
Reviewers: bengotow
Reviewed By: bengotow
Differential Revision: https://review.inboxapp.com/D1157
