When searching only message bodies, we skipped headers completely so body decoding didn't work for non-ASCII.
When searching only message bodies, we skipped headers completely so body
decoding didn't work for non-ASCII.

--HG--
branch : HEAD

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