[xkb] Do XkbKSIsLower() and XkbKSIsUpper() matter?

[Ran Benita]

On Sat, Oct 26, 2013 at 02:04:55PM -0700, Alan Coopersmith wrote:
> Does anyone know of any reason to waste time on this function?  Can we just
> delete it altogther now?   (libxkbfile is undocumented, and was originally
> considered private API, but we know software like GNOME has used it in the
> past.)

It is used at one point in libxkbfile, FindTypeForKey. Anyway, I don't
see any reason to risk removing it; just replace it with a simple call
to XConvertCase from libX11, e.g. in libxkbcommon we have

    bool
    xkb_keysym_is_lower(xkb_keysym_t ks)
    {
        xkb_keysym_t lower, upper;

        XConvertCase(ks, &lower, &upper);

        if (lower == upper)
            return false;

        return (ks == lower ? true : false);
    }

(XConverCase is copied for libX11) and we haven't had any complaints.