Bug 1058459 - [SMS] Data shared from other applications are not shown as Drafts until the app is killed and open again.  r=schung

Using localStorage as inter app communication bus.
I found another issue about draft discard but it is not related to your patch:
1) Press home to autosave the draft in other activity,
2) Resume activity, edit the message and discard
3) Switch back to message app, the draft is still there.

I've seen other strange behavior after autosaving like duplicate draft added, but I think the issue is already there even without your patch(which means you could see these bugs after message app reopen, if you don't have iac). Just make sure you also faced these bug related to autosave cross activity.