Function: set-window-scroll-bars

Set width and type of scroll bars of window WINDOW.
WINDOW must be a live window and defaults to the selected one.

Second parameter WIDTH specifies the pixel width for the scroll bar;
this is automatically adjusted to a multiple of the frame column width.
Third parameter VERTICAL-TYPE specifies the type of the vertical scroll
bar: left, right, or nil.
If WIDTH is nil, use the frame's scroll-bar width.
If VERTICAL-TYPE is t, use the frame's scroll-bar type.
Fourth parameter HORIZONTAL-TYPE is currently unused.