[gnome-control-center] display: fix accidentally commented out code

[Cosimo Cecchi <cosimoc src gnome org>]

commit 1af73218fc3f97a3e0617c3c16605351c3a6332b
Author: Cosimo Cecchi <cosimo endlessm com>
Date:   Thu Jun 9 17:02:47 2016 -0700

    display: fix accidentally commented out code
    
    Not sure why I commented this out before pushing 47dcfee8 -- whoops!

 panels/display/cc-display-panel.c |    7 +++----
 1 files changed, 3 insertions(+), 4 deletions(-)
---
diff --git a/panels/display/cc-display-panel.c b/panels/display/cc-display-panel.c
index bb9dedc..72720fa 100644
--- a/panels/display/cc-display-panel.c
+++ b/panels/display/cc-display-panel.c
@@ -2362,10 +2362,9 @@ show_setup_dialog (CcDisplayPanel *panel)
   gtk_widget_set_halign (priv->res_combo, GTK_ALIGN_START);
 
   /* overscan */
-  /* if (!gnome_rr_output_is_builtin_display (output) && */
-  /*     gnome_rr_output_supports_underscanning (output)) */
-
-  {
+  if (!gnome_rr_output_is_builtin_display (output) &&
+      gnome_rr_output_supports_underscanning (output))
+    {
       priv->scaling_switch = gtk_switch_new ();
       gtk_switch_set_active (GTK_SWITCH (priv->scaling_switch),
                              gnome_rr_output_info_get_underscanning (priv->current_output));