imap-quota: Iterate quota roots only once when replying to GETQUOTAROOT. This halves the required dict lookup count.
imap-quota: Iterate quota roots only once when replying to GETQUOTAROOT.
This halves the required dict lookup count.

--HG--
branch : HEAD

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