[gtk] print operation: Use standard class padding

[Matthias Clasen <matthiasc src gnome org>]

commit cc1c1df405e16b907d6b18c0b8863310ce65a1ad
Author: Matthias Clasen <mclasen redhat com>
Date:   Sun May 26 22:24:37 2019 +0000

    print operation: Use standard class padding

 gtk/gtkprintoperation.h | 10 +---------
 1 file changed, 1 insertion(+), 9 deletions(-)
---
diff --git a/gtk/gtkprintoperation.h b/gtk/gtkprintoperation.h
index 3ae0ed4924..c10ba4b7b9 100644
--- a/gtk/gtkprintoperation.h
+++ b/gtk/gtkprintoperation.h
@@ -186,15 +186,7 @@ struct _GtkPrintOperationClass
 
   /*< private >*/
 
-  /* Padding for future expansion */
-  void (*_gtk_reserved1) (void);
-  void (*_gtk_reserved2) (void);
-  void (*_gtk_reserved3) (void);
-  void (*_gtk_reserved4) (void);
-  void (*_gtk_reserved5) (void);
-  void (*_gtk_reserved6) (void);
-  void (*_gtk_reserved7) (void);
-  void (*_gtk_reserved8) (void);
+  gpointer padding[8];
 };
 
 /**