gtk/tree_view.go
func (v *TreeView) SetShowExpanders(show bool) {
	C.gtk_tree_view_set_show_expanders(v.native(), gbool(show))
}
func (v *TreeView) SetShowExpanders(show bool) {
	C.gtk_tree_view_set_show_expanders(v.native(), gbool(show))
}
// SetShowExpanders is a wrapper around gtk_tree_view_set_show_expanders().