bug#19395: 25.0.50; Setting left fringe to 0 messes up window-width

[Eli Zaretskii]

> Date: Sat, 20 Dec 2014 16:06:21 +0100
> From: martin rudalics <rudalics@gmx.at>
> CC: 19395@debbugs.gnu.org
> 
> The faces apparently _get_ merged dependent on the buffer _and_ the
> frame.

Remapped faces might depend on the buffer, non-remapped ones depend
only on the frame.

> I need a corresponding `window-char-height' as well, probably also with
> a FACE argument.

Without the FACE argument, you already have default-font-height,

>  > For completeness, it probably also makes sense to include the following
>  > function in simple.el, which already has a function
>  > `default-font-height'.
>  >
>  > (defun default-font-width ()
>  >    "Return the width in pixels of the current buffer's default face font.
> 
> I profoundly dislike the "default-" prefix here.  `buffer-font-height'
> and `buffer-font-width' would be much better IMHO.

But a buffer can use a variety of fonts.