bug#30692: list-buffers has hardwired 80 character width from the 80's

[Robert Pluim]

>>>>> On Fri, 07 Aug 2020 11:03:43 +0200, Lars Ingebrigtsen <larsi@gnus.org> 
>>>>> said:
    >> Ah, I see.  Yes, that's pretty annoying.  It should expand the buffer
    >> column size based on the window width.

    Lars> To recap: Even when the window is very wide, `C-x b' renders with

    Lars> Buffer-menu-name-width 19

    Lars> I propose to allow nil as a value here (and default Emacs to it), and
    Lars> nil would then mean "compute based on window width".  The computation
    Lars> would end up with 19 as the result if the window is 80 characters 
long,
    Lars> but progressively make it longer if the window is wider (according to
    Lars> some curve), but never make it longer than actual buffer names 
displayed.

    Lars> Does this sound reasonable to everybody?

Better. This sounds like "why the hell aren't we doing this already".

+1 from me

Robert