bug#19802: 24.4.90; set-background-color does nothing in -nw sessions

[Eli Zaretskii <eliz@gnu.org>]

> Date: Sat, 07 Feb 2015 13:24:13 +0200
> From: Eli Zaretskii <eliz@gnu.org>
> 
> To reproduce:
> 
>   emacs -Q -nw
>   M-x set-background-color RET blue RET
> 
> This appears to have no effect at all.  Even the 'background-color'
> frame parameter stays at its default "unspecified-bg" value, even
> though the code of set-background-color explicitly modifies the
> frame's parameters:
> 
>   (defun set-background-color (color-name)
>     "Set the background color of the selected frame to COLOR-NAME.
>   When called interactively, prompt for the name of the color to use.
>   To get the frame's current background color, use `frame-parameters'."
>     (interactive (list (read-color "Background color: ")))
>     (modify-frame-parameters (selected-frame)
> 			     (list (cons 'background-color color-name)))
>     (or window-system
> 	(face-set-after-frame-default (selected-frame))))
> 
> Looks like this has been broken since 24.1, as the last version in
> which I see it working is 23.4.  I tried both on GNU/Linux and on
> MS-Windows, with the same result.

Fixed with these commits:

 20c817d and a7b1c2f on the emacs-24 branch
 dd2aa93 on master