pub unsafe extern "C" fn gtk_viewport_new(
hadjustment: *mut GtkAdjustment,
vadjustment: *mut GtkAdjustment,
) -> *mut GtkWidgetpub unsafe extern "C" fn gtk_viewport_new(
hadjustment: *mut GtkAdjustment,
vadjustment: *mut GtkAdjustment,
) -> *mut GtkWidget