gdbusactiongroup: Add prototype for g_dbus_action_group_sync()

Even private functions that are actually called across compilation
units should have prototypes.  For g_dbus_action_group_sync(), create
one in gdbusactiongroup-private.h

https://bugzilla.gnome.org/show_bug.cgi?id=687385

gio/Makefile.am

@@ -174,6 +174,7 @@ application_sources = \
 	gsimpleactiongroup.c			\
 	gremoteactiongroup.c			\
 	gactiongroupexporter.c			\
+	gdbusactiongroup-private.h		\
 	gdbusactiongroup.c			\
 	gaction.c				\
 	gsimpleaction.c				\

gio/gactiongroupexporter.c

@@ -45,7 +45,7 @@
  * g_dbus_action_group_get() to obtain a #GDBusActionGroup.
  */
 
-G_GNUC_INTERNAL GVariant *
+static GVariant *
 g_action_group_describe_action (GActionGroup *action_group,
                                 const gchar  *name)
 {

gio/gapplicationimpl-dbus.c

@@ -24,7 +24,7 @@
 #include "gactiongroup.h"
 #include "gactiongroupexporter.h"
 #include "gremoteactiongroup.h"
-#include "gdbusactiongroup.h"
+#include "gdbusactiongroup-private.h"
 #include "gapplication.h"
 #include "gfile.h"
 #include "gdbusconnection.h"
@@ -37,12 +37,6 @@
 #include "gapplicationcommandline.h"
 #include "gdbusmethodinvocation.h"
 
-G_GNUC_INTERNAL gboolean
-g_dbus_action_group_sync (GDBusActionGroup  *group,
-                          GCancellable      *cancellable,
-                          GError           **error);
-
-
 /* DBus Interface definition {{{1 */
 
 /* For documentation of these interfaces, see

gio/gdbusactiongroup-private.h

@@ -0,0 +1,37 @@
+/*
+ * Copyright © 2010 Codethink Limited
+ * Copyright © 2011 Canonical Limited
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published
+ * by the Free Software Foundation; either version 2 of the licence or (at
+ * your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General
+ * Public License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
+ * Boston, MA 02111-1307, USA.
+ *
+ * Authors: Ryan Lortie <desrt@desrt.ca>
+ */
+
+#ifndef __G_DBUS_ACTION_GROUP_PRIVATE_H__
+#define __G_DBUS_ACTION_GROUP_PRIVATE_H__
+
+#include "gdbusactiongroup.h"
+
+G_BEGIN_DECLS
+
+gboolean
+g_dbus_action_group_sync (GDBusActionGroup  *group,
+                          GCancellable      *cancellable,
+                          GError           **error);
+
+G_END_DECLS
+
+#endif 

gio/gdbusactiongroup.c

@@ -22,7 +22,7 @@
 
 #include "config.h"
 
-#include "gdbusactiongroup.h"
+#include "gdbusactiongroup-private.h"
 
 #include "gremoteactiongroup.h"
 #include "gdbusconnection.h"