bug in frame-width

[Luc Teirlinck]

I believe the following is an outright bug.

Do `emacs -q &'

ELISP> (frame-width)
80

Indeed, exacly 80 characters fit on the screen.

ELISP> (fringe-mode 0)
nil

Now 83 characters fit on the screen.  But we still get:

ELISP> (frame-width)
80

Unless there is something I completely fail to understand, that should
be 83.

Sincerely,

Luc.