bug#11464: 24.1.50; pos-visible-in-window-p returns a false positive with bidi text

[Eli Zaretskii]

> From: Ari Roponen <ari.roponen@gmail.com>
> Date: Sun, 13 May 2012 18:54:59 +0300
> 
> The following code shows a problem with pos-visible-in-window-p
> and bidirectional text. When there are right-to-left characters
> at the beginning of the buffer, the function returns nil, as the
> last line is not visible. However, when "a" is inserted into the
> beginning of the buffer, the function returns t, which is
> incorrect.

Sigh... where are you guys on weekends, when I _really_ have time to
work on Emacs?...

> The bug happens in trunk and emacs-24, but not in emacs-23, so it
> could be considered as a regression ;-)

Nothing that's related to R2L text in a left-to-right paragraph can
ever be a regression wrt Emacs 23.

But since the fix is quite simple, here you go: fixed in revision
107994 on the emacs-24 branch.

Thanks.