use g_slice_new0 instead of panel_slice_new0 (depreciated)

panel-plugin/buttons/wckbuttons.c

@@ -138,7 +138,7 @@ wckbuttons_new (XfcePanelPlugin *plugin)
   GtkWidget      *label;
 
   /* allocate memory for the plugin structure */
-  wb = panel_slice_new0 (WBPlugin);
+  wb = g_slice_new0 (WBPlugin);
 
   /* pointer to plugin */
   wb->plugin = plugin;
@@ -189,7 +189,7 @@ wckbuttons_free (XfcePanelPlugin *plugin, WBPlugin    *wb)
     g_free (wb->setting1);
 
   /* free the plugin structure */
-  panel_slice_free (WBPlugin, wb);
+  g_slice_free (WBPlugin, wb);
 }
 
 

panel-plugin/title/windowck.c

@@ -80,7 +80,7 @@ static void windowck_read(WindowckPlugin *wckp) {
     const gchar *title_font;
 
     /* allocate memory for the preferences structure */
-    wckp->prefs = panel_slice_new0(WCKPreferences);
+    wckp->prefs = g_slice_new0(WCKPreferences);
 
     /* get the plugin config file location */
     file = xfce_panel_plugin_save_location(wckp->plugin, TRUE);