Scroll bars on macOS builds

[Angelo Graziosi]

It seems I do not see the scroll bars on macOS builds even if in my init.el I 
have (for a long time) 

(horizontal-scroll-bar-mode 1)

also the vertical bar is absent and with buffers with a lot of lines the only 
way to know in which "position" one is along the buffer is to read the 
indication on the mode line, xy%. 

Being a GUI build, one expects to get a GUI indication of this, with the 
vertical scroll bar, for example...

I build master monthly on macOS 10.13.6, the last version I can use on this 
MBP, and configuring with

./configure --with-ns \
            --without-dbus \
            --without-pop \
            --with-modules


Happy New Year!

Ciao,
 Angelo.