bug#7782: 24.0.50; 24.0.50: set-scroll-bar-mode missing under non-GUI environments

[Tim Cross <theophilusx@gmail.com>]

According to the documentation for scroll-bar-mode, the way to
set/change scroll-bar settings from within elisp code is to use the
set-scroll-bar-mode function. However, this function is only defined
when run under graphic capable environments, such as X, but not in other
environments such as the Linux console. 

This means that if you don't want your elisp or .emacs to raise an
error, you also need to wrap calls to this function inside something
like (when display-graphic-p ...). This is not required for other
display related functions that depend on an environment requiring
support for graphics i.e. tool-bar-mode. 

For consistency and to help reduce environment related bugs, I would
like to request a feature enhancement whereby set-scroll-bar-mode is
defined in all environmennts, even if it is just a stub / do nothing
operation in environments that do not support scroll bars. 

thanks,

Tim

In GNU Emacs 24.0.50.1 (x86_64-unknown-linux-gnu, GTK+ Version 2.22.0)
 of 2011-01-04 on puma
Windowing system distributor `The X.Org Foundation', version 11.0.10900000
configured using `configure  '--prefix=/usr/local''