bug#19769: 25.0.50; Incorrect beginning of line in visual-line-mode

[Eli Zaretskii]

> Date: Wed, 04 Feb 2015 18:01:01 +0200
> From: Eli Zaretskii <eliz@gnu.org>
> Cc: 19769@debbugs.gnu.org
> 
> The problem is in vertical-motion (or its subroutines, I didn't yet
> look deeper), and it's a regression in the emacs-24 branch wrt Emacs
> 24.3.  So we should fix it before the release.

Fixed in commit c0ba590 on the emacs-24 branch, please test.

For the record, quite a few functions misbehaved in this situation,
including posn-at-point.