bug#23690: 25.0.94; Window resizing regression

[martin rudalics]

> 0. emacs -Q
> 1. Type `C-x 3' to split the selected window into two side-by-side
>     windows.
> 2. Sanity check: click mouse-1 on the divider between the mode lines,
>     and observe that by dragging the mouse you can move the vertical
>     boundary between the windows to the left or right.
> 3. In the menu Options->Show/Hide->Scroll-bar click the "On the Left"
>     button to make the scroll bars appear on the left side of the
>     windows.
> 4. Repeat step 2.
> => The vertical boundary between the windows does not change, but
>     instead the echo area displays the message "No window on the right of
>     this one" (although the selected window is the one on the left).
>
> This is a regression from Emacs 24.5, where step 4 works just like step
> 2.  Git bisect identifies the following as the responsible commit:
>
> commit 3110159d1fb6b6071803355951d9ae314095df36
> Author: Martin Rudalics <rudalics@gmx.at>
> Date:   Fri Oct 24 11:58:43 2014 +0200
>
>      Improve mouse dragging of frame edges.
>
>      * keyboard.c (make_lispy_position): Return coordinates also when
>      on scroll bars, fringes, margins or not in a window.
>      * xdisp.c (show_mouse_face): Don't change cursor face during
>      mouse tracking.
>      * mouse.el (mouse-drag-line): Don't use mouse-pixel-position.
>      Calculate increment from last position instead of window edge.
>      Add right- and bottom-divider bindings to transient map.

Would the attached patch fix it for you?

Thanks, martin

mouse.diff
Description: Text document