comment for "fast promote"

Hi,

Now I'm seeing xlog.c in 93_stable for studying "fast promote",
and I have a question.

I think it has an extra unlink command for "promote" file.
(on 9937 line)
-------
9934 if (stat(FAST_PROMOTE_SIGNAL_FILE, &stat_buf) == 0)
9935 {
9936 unlink(FAST_PROMOTE_SIGNAL_FILE);
9937 unlink(PROMOTE_SIGNAL_FILE);
9938 fast_promote = true;
9939 }
-------

Is this command necesary ?

regards,
------------------
NTT Software Corporation
Tomonari Katsumata