bug#60886: 29.0.60; split-root-window-below broken for split-window-keep-point

[Juri Linkov <juri@linkov.net>]

> Just think of how much easier it would have been, had these new
> functions been coded as
>
> (defun split-root-window-below (&optional size)
>   "Split root window of selected frame in two.
> The current window configuration is retained in the top window,
> the lower window takes up the whole width of the frame.  SIZE is
> handled as in `split-window-below'.  The buffer of the new window is
> taken from the selected window."
>   (interactive "P")
>   (when (and size (< size 0) (< (- size) window-min-height))
>     ;; `split-window' would not signal an error here.
>     (error "Size of new window too small"))
>   (split-window (frame-root-window) size 'below))
>
> (defun split-root-window-right (&optional size)
>   "Split root window of selected frame into two side-by-side windows.
> The current window configuration is retained within the left
> window, and a new window is created on the right, taking up the
> whole height of the frame.  SIZE is treated as by
> `split-window-right'.  The buffer of the new window is taken from
> the selected window."
>   (interactive "P")
>   (when (and size (< size 0) (< (- size) window-min-width))
>     ;; `split-window' would not signal an error here.
>     (error "Size of new window too small"))
>   (split-window (frame-root-window) size 'right))

I proposed the same in bug#56767.