[gtk/gtk-2-24: 1/2] Fix compiler warnings with GCC 8.1.

[Benjamin Otte <otte src gnome org>]

commit 889a63dffc72c048502d0f7d2b26bfc8532462eb
Author: John Lindgren <john jlindgren net>
Date:   Tue May 15 21:47:12 2018 -0400

    Fix compiler warnings with GCC 8.1.
    
    GCC 8.1 added some new warnings, including warning about parentheses
    with no effect in variable declarations.  GTK2 headers have a few of
    these, which produce a lot of warnings in projects using GTK2.
    
    The warnings look like:
    /usr/include/gtk-2.0/gtk/gtkfilechooserbutton.h:59:8: warning:
    unnecessary parentheses in declaration of ‘__gtk_reserved1’ [-Wparentheses]
       void (*__gtk_reserved1);
            ^
    
    Removing the parentheses is harmless and fixes the warnings.

 gtk/gtkfilechooserbutton.h | 14 +++++++-------
 gtk/gtkstatusicon.h        |  4 ++--
 2 files changed, 9 insertions(+), 9 deletions(-)
---
diff --git a/gtk/gtkfilechooserbutton.h b/gtk/gtkfilechooserbutton.h
index b3d9112cf9..fdacc4b6ec 100644
--- a/gtk/gtkfilechooserbutton.h
+++ b/gtk/gtkfilechooserbutton.h
@@ -56,13 +56,13 @@ struct _GtkFileChooserButtonClass
 
   void (* file_set) (GtkFileChooserButton *fc);
 
-  void (*__gtk_reserved1);
-  void (*__gtk_reserved2);
-  void (*__gtk_reserved3);
-  void (*__gtk_reserved4);
-  void (*__gtk_reserved5);
-  void (*__gtk_reserved6);
-  void (*__gtk_reserved7);
+  void *__gtk_reserved1;
+  void *__gtk_reserved2;
+  void *__gtk_reserved3;
+  void *__gtk_reserved4;
+  void *__gtk_reserved5;
+  void *__gtk_reserved6;
+  void *__gtk_reserved7;
 };
 
 
diff --git a/gtk/gtkstatusicon.h b/gtk/gtkstatusicon.h
index 19dbd1cdeb..c45caca5ae 100644
--- a/gtk/gtkstatusicon.h
+++ b/gtk/gtkstatusicon.h
@@ -73,8 +73,8 @@ struct _GtkStatusIconClass
                                      gboolean        keyboard_mode,
                                      GtkTooltip     *tooltip);
 
-  void (*__gtk_reserved1);
-  void (*__gtk_reserved2);
+  void *__gtk_reserved1;
+  void *__gtk_reserved2;
 };
 
 GType                 gtk_status_icon_get_type           (void) G_GNUC_CONST;