bug#25408: Remove Decorations Around Emacs Frame (NS port)

[martin rudalics]

> I made an attempt at adapting/modernizing my "multicolumn" (
> https://github.com/Lindydancer/multicolumn) package (which, among else, can
> resize and reposition a frame). Currently, I have hardcoded the title size
> for various systems -- on macOS I use "24". However, `frame-geometry' says
> that the title height is 22 pixels. I'm not sure how to account for the
> missing 2 pixels, any thoughts?

The value returned by ‘frame-geometry’ should be correct.  Look at all
the occurrences of FRAME_NS_TITLEBAR_HEIGHT in nsterm.m.  In contrast
with other platforms, NS uses that value internally all the time.

> Martin, I also notices that `menu-bar-external' says `nil', but I guess is
> should say non-nil, right?

Right.  It should say non-nil.

If possible, however, please check the function ‘ns-frame-edges’ for all
values of TYPE whether it handles the menu bar height correctly, i.e.,
ignores it.

Thanks, martin