kSeen
IMAP::kSeen, nextFlags);
else if ((flags & IMAP::kSeen) != 0)
flags &= ~(IMAP::kAnswered | IMAP::kSeen);
flags |= IMAP::kAnswered | IMAP::kSeen;
flags |= IMAP::kSeen;
flags |= IMAP::kFlagged | IMAP::kSeen;
if ((flags & IMAP::kSeen) != 0)
flags |= IMAP::kSeen;