mbox-snarf: Keep the mailbox locked while snarfing to avoid duplicates.
mbox-snarf: Keep the mailbox locked while snarfing to avoid duplicates.

--HG--
branch : HEAD

jwm/dovecot-notmuch,jwm/dovecot-notmuch,jkerihuel/dovecot,jwm/dovecot-notmuch,jwm/dovecot-notmuch,jwm/dovecot-notmuch,jkerihuel/dovecot,jkerihuel/dovecot,jkerihuel/dovecot,jkerihuel/dovecot