bug#9530: 24.0.50; incorrect cursor moving

[Eli Zaretskii]

> From: Kenichi Handa <handa@m17n.org>
> Date: Sat, 17 Sep 2011 21:41:31 +0900
> 
> % emacs -Q
> ;; Now we are in *scratch* buffer which contains ";; This
> bufffer is..." comment at the head.
> ESC : (insert (propertize "\t" 'display '(space :align-to 77)) "a 
> "(propertize "\t" 'display '(space :align-to 79)) "b") RET
> ;; Now the last line fo *scratch* buffer is showing "a" at
> ;; column 77, and showingg "b" at column 0 of the continuing line.
> C-a C-f C-f
> ;; The cursor is at the right of character "a".  This is normal.
> C-f
> ;; The cursor jumps to the end of the first line;
> ;; i.e. the right of "for List evaluation."
> C-f
> ;; The cursor moves back to the character "b" of the
> ;; original line; i.e. the line inserted by the above "ESC : ... RET".

Fixed in revision 105808 on the trunk.