[gnome-control-center/benzea/display-more-error-handling: 25/25] display: Add guards for NULL display configuration

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit 345a819f84853ec331e7ae2f522a046cca96951a
Author: Benjamin Berg <bberg redhat com>
Date:   Wed Jul 3 09:53:38 2019 +0200

    display: Add guards for NULL display configuration
    
    This may happen under some conditions. Possibly due to a race condition
    (i.e. we did not receive any configuration from mutter yet) or also if
    we are not running on GNOME.
    
    Add guards for NULL configuration. This configuration is never
    applicable and mostly clears the UI.
    
    Fixes: #604

 panels/display/cc-display-panel.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)
---
diff --git a/panels/display/cc-display-panel.c b/panels/display/cc-display-panel.c
index 3469fd7ac..701728376 100644
--- a/panels/display/cc-display-panel.c
+++ b/panels/display/cc-display-panel.c
@@ -745,6 +745,12 @@ rebuild_ui (CcDisplayPanel *panel)
   g_list_store_remove_all (panel->primary_display_list);
   gtk_list_store_clear (panel->output_selection_list);
 
+  if (!panel->current_config)
+    {
+      panel->rebuilding_counter--;
+      return;
+    }
+
   n_active_outputs = 0;
   n_usable_outputs = 0;
   outputs = cc_display_config_get_ui_sorted_monitors (panel->current_config);
@@ -987,6 +993,12 @@ update_apply_button (CcDisplayPanel *panel)
   gboolean config_equal;
   g_autoptr(CcDisplayConfig) applied_config = NULL;
 
+  if (!panel->current_config)
+    {
+      reset_titlebar (panel);
+      return;
+    }
+
   applied_config = cc_display_config_manager_get_current (panel->manager);
 
   config_equal = cc_display_config_equal (panel->current_config,