On small window sizes the ButtonBox can overflow the panel. This is
especially true in single display mode when no other elemnts prevent
shrinking to e.g. 360px width on phones. Use the ComboBox introduced in
632cb3c907 in these cases.
For that we introduce cc_display_settings_refresh_layout() to refresh
the layout when the folded state changes. This can later on be used for
more tweaks to shrink to smaller sizes.
