bug#64417: 30.0.50; keymap-unset :REMOVE keyword not working

[Eli Zaretskii]

> From: German Pacenza <germanp82@hotmail.com>
> Date: Sun, 02 Jul 2023 08:46:28 -0300
> 
> 
> When I evaluate:
> (keymap-unset diff-mode-map "M-SPC" :REMOVE)
> M-SPC still runs scroll-up-command
> 
> (keymap-unset diff-mode-map "M-SPC")
> M-SPC is removed from diff-mode-map and cycle-spacing (global-mode-map)
> is activated
> 
> This contradicts the keymap-unset docstring:
> 
> If REMOVE, remove the binding instead of unsetting it.  This only
> makes a difference when there’s a parent keymap.  When unsetting
> a key in a child map, it will still shadow the same key in the
> parent keymap.  Removing the binding will allow the key in the
> parent keymap to be used.

But:

  (keymap-parent diff-mode-map) => nil