[gtk] check button: Use standard padding

[Matthias Clasen <matthiasc src gnome org>]

commit a29fe385df1468b042943792884fd91761ab3501
Author: Matthias Clasen <mclasen redhat com>
Date:   Mon May 27 04:09:41 2019 +0000

    check button: Use standard padding

 gtk/gtkcheckbutton.h | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)
---
diff --git a/gtk/gtkcheckbutton.h b/gtk/gtkcheckbutton.h
index b1e46820de..9a7ed350f7 100644
--- a/gtk/gtkcheckbutton.h
+++ b/gtk/gtkcheckbutton.h
@@ -55,11 +55,9 @@ struct _GtkCheckButtonClass
 {
   GtkToggleButtonClass parent_class;
 
-  /* Padding for future expansion */
-  void (*_gtk_reserved1) (void);
-  void (*_gtk_reserved2) (void);
-  void (*_gtk_reserved3) (void);
-  void (*_gtk_reserved4) (void);
+  /*< private >*/
+
+  gpointer padding[8];
 };