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

[Eli Zaretskii]

> Date: Sun, 12 Dec 2010 16:15:04 +0900
> From: YAMAMOTO Mitsuharu <mituharu@math.s.chiba-u.ac.jp>
> 
> >>>>> On Sat, 13 Nov 2010 23:10:56 +0200, Eli Zaretskii <eliz@gnu.org> said:
> 
> > I see that Chong modified picture.el to not use posn-col-row.  But I
> > think that posn-col-row should pay attention to the existence of the
> > header line, so I fixed that as well (on the emacs-23 branch).
> 
> Perhaps `header-line-height' should be enclosed with
> (with-current-buffer (window-buffer window) ...) as in the case of
> `line-spacing'?

What would be the use-cases where this is necessary?