bug#16647: Imprecisions with window-resizing cursors

[martin rudalics]

> But with
>
>     emacs -Q
>     M-: (set-frame-parameter nil 'bottom-divider-width 10) RET
>     M-x split-window-below RET
>     Drag the window divider up a few pixels (but less than one line)
>     Observe bug
>     M-: (setq window-resize-pixelwise t)
>
> The bug is no longer observed. Note that I didn't move the divider after
> setting window-resize-pixelwise, the bug was immediately no longer
> manifest.

OK.  Can you try the same I asked Evgeni?  In xdisp.c remove this code

  if (window_resize_pixelwise)
    {
      width = height = 1;
      goto virtual_glyph;
    }

and check whether setting `window-resize-pixelwise' to t still changes
the behavior.  The expected answer is "no".

Thanks, martin