[gnome-panel] panel-screensaver: avoid deprecated g_type_class_add_private

[Alberts Muktupāvels <muktupavels src gnome org>]

commit 9a7aec5a9db3c38ab7102266834d445567013fd9
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Thu Sep 13 02:33:20 2018 +0300

    panel-screensaver: avoid deprecated g_type_class_add_private

 gnome-panel/libpanel-util/panel-screensaver.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)
---
diff --git a/gnome-panel/libpanel-util/panel-screensaver.c b/gnome-panel/libpanel-util/panel-screensaver.c
index 336576b65..d249c066c 100644
--- a/gnome-panel/libpanel-util/panel-screensaver.c
+++ b/gnome-panel/libpanel-util/panel-screensaver.c
@@ -30,13 +30,11 @@ struct _PanelScreensaverPrivate {
        GDBusProxy *proxy;
 };
 
-G_DEFINE_TYPE (PanelScreensaver, panel_screensaver, G_TYPE_OBJECT);
+G_DEFINE_TYPE_WITH_PRIVATE (PanelScreensaver, panel_screensaver, G_TYPE_OBJECT)
 
 static void
 panel_screensaver_class_init (PanelScreensaverClass *klass)
 {
-       g_type_class_add_private (klass,
-                                 sizeof (PanelScreensaverPrivate));
 }
 
 static void
@@ -44,9 +42,7 @@ panel_screensaver_init (PanelScreensaver *screensaver)
 {
        GError *error;
 
-       screensaver->priv = G_TYPE_INSTANCE_GET_PRIVATE (screensaver,
-                                                        PANEL_TYPE_SCREENSAVER,
-                                                        PanelScreensaverPrivate);
+       screensaver->priv = panel_screensaver_get_instance_private (screensaver);
 
        error = NULL;
        screensaver->priv->proxy = g_dbus_proxy_new_for_bus_sync (