bug#7390: 24.0.50; pos-col-row gives incorrect row

[Eli Zaretskii]

> Date: Sat, 13 Nov 2010 23:10:56 +0200
> From: Eli Zaretskii <eliz@gnu.org>
> Cc: 
> 
> I think that posn-col-row should pay attention to the existence of
> the header line

E.g., artist.el is broken in the same way as picture.el, when there's
a header line in the window where you draw.

Many users of posn-col-row only use it to compute the difference
between two rows -- those will be unaffected by my change in
posn-col-row.

So I still maintain that the fix in posn-col-row should stay in the
emacs-23 branch.