Sets the scrollbar policy for the horizontal and vertical scrollbars.
The policy determines when the scrollbar should appear; it is a value
from the GtkPolicyType enumeration. If GTK_POLICY_ALWAYS, the
scrollbar is always present; if GTK_POLICY_NEVER, the scrollbar is
never present; if GTK_POLICY_AUTOMATIC, the scrollbar is present only
if needed (that is, if the slider part of the bar would be smaller
than the trough — the display is larger than the page size).
Sets the scrollbar policy for the horizontal and vertical scrollbars.
The policy determines when the scrollbar should appear; it is a value from the GtkPolicyType enumeration. If GTK_POLICY_ALWAYS, the scrollbar is always present; if GTK_POLICY_NEVER, the scrollbar is never present; if GTK_POLICY_AUTOMATIC, the scrollbar is present only if needed (that is, if the slider part of the bar would be smaller than the trough — the display is larger than the page size).