bug#14591: New keyword :local for defcustom

[Juanma Barranquero]

> But: is it important for those to be "not automatically buffer-local",
> or would it be OK for them to be automatically buffer-local.

Well, that's a good question.

The first example I can think of is one variable I'm really puzzled is
not automatically buffer-local, because it is *always* used as so (I
checked), revert-buffer-function. The only case in the sources where
it is not assigned with (set (make-local-variable
'revert-buffer-function) ...) is in dired-x.el, and that because at
that point is already guaranteed that dired-mode.el made it a-b-l.

So, it's important for revert-buffer-function to be "not automatically
buffer-local"? Does it even make sense that it is not? :-)

   J