Add compatibility with GTK+ 2.18

To replace all calls to deprecated code, GTK+ 2.20 is required - add
some basic compatibility code, so that is still possible to build the
shell with GTK+ 2.18 when not using -DGSEAL_ENABLE.

https://bugzilla.gnome.org/show_bug.cgi?id=618258

src/Makefile-tray.am

@@ -15,6 +15,7 @@ TRAY_STAMP_FILES = stamp-na-marshal.h
 
 # please, keep this sorted alphabetically
 tray_source =			\
+	gtk-compat.h		\
 	tray/na-tray-child.c	\
 	tray/na-tray-child.h	\
 	tray/na-tray-manager.c	\

src/Makefile.am

@@ -82,6 +82,7 @@ libgnome_shell_la_SOURCES =		\
 	$(shell_built_sources)		\
 	$(shell_public_headers_h)	\
 	gnome-shell-plugin.c		\
+	gtk-compat.h			\
 	shell-app.c			\
 	shell-app-private.h		\
 	shell-app-system.c		\

src/gtk-compat.h

@@ -0,0 +1,19 @@
+#ifndef __GTK_COMPAT_H__
+#define __GTK_COMPAT_H__
+
+#include <gtk/gtk.h>
+
+/* Provide a compatibility layer for accessor functions introduced
+ * in GTK+ 2.20 which we need to build with GSEAL_ENABLE.
+ * That way it is still possible to build with GTK+ 2.18 when not
+ * using GSEAL_ENABLE
+ */
+
+#if !GTK_CHECK_VERSION(2, 20, 0)
+
+#define gtk_widget_get_realized(w) GTK_WIDGET_REALIZED (w)
+#define gtk_widget_get_mapped(w)   GTK_WIDGET_MAPPED (w)
+
+#endif /* GTK_CHECK_VERSION(2, 20, 0) */
+
+#endif /* __GTK_COMPAT_H__ */

src/shell-embedded-window.c

@@ -6,6 +6,7 @@
 #include <clutter/x11/clutter-x11.h>
 
 #include "shell-embedded-window-private.h"
+#include "gtk-compat.h"
 
 /* This type is a subclass of GtkWindow that ties the window to a
  * ShellGtkEmbed; the window is reparented into the stage

src/shell-gtk-embed.c

@@ -3,6 +3,7 @@
 #include "config.h"
 
 #include "shell-embedded-window-private.h"
+#include "gtk-compat.h"
 
 #include <clutter/glx/clutter-glx.h>
 #include <clutter/x11/clutter-x11.h>

src/tray/na-tray-child.c

@@ -23,6 +23,7 @@
 #include <string.h>
 
 #include "na-tray-child.h"
+#include "gtk-compat.h"
 
 #include <glib/gi18n-lib.h>
 #include <gdk/gdk.h>

src/tray/na-tray-manager.c

@@ -25,6 +25,7 @@
 #include <libintl.h>
 
 #include "na-tray-manager.h"
+#include "gtk-compat.h"
 
 #include <gdkconfig.h>
 #include <glib/gi18n-lib.h>