Notmuch server-side threading added messages within a thread that didn't
match the query into the uidstore. By doing so, several UI issues
presented:
* All "hidden" messages displayed at the bottom of the msglist
* Selected messages wouldn't open properly
This patch stops these messages from being put into the message store,
thereby resolving the UI issues
Signed-off-by: Tim Culverhouse <tim@timculverhouse.com>
Acked-by: Koni Marti <koni.marti@gmail.com>