acl: Update acl_dict correctly also for other visible users' shared namespaces.
acl: Update acl_dict correctly also for other visible users' shared namespaces.

--HG--
branch : HEAD

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