[gnome-flashback] monitor-manager: don't throw an error if UPower isn't running

[Alberts Muktupāvels <muktupavels src gnome org>]

commit cc7cf98713a2df6508959d7289898a2291c5566f
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Tue Jul 16 21:29:11 2019 +0300

    monitor-manager: don't throw an error if UPower isn't running
    
    Based on mutter commit:
    https://gitlab.gnome.org/GNOME/mutter/commit/644a618fb15d90056107

 backends/gf-monitor-manager.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)
---
diff --git a/backends/gf-monitor-manager.c b/backends/gf-monitor-manager.c
index f1ba8b1..6462f6e 100644
--- a/backends/gf-monitor-manager.c
+++ b/backends/gf-monitor-manager.c
@@ -2020,8 +2020,11 @@ gf_monitor_manager_constructed (GObject *object)
     {
       manager->up_client = up_client_new ();
 
-      g_signal_connect_object (manager->up_client, "notify::lid-is-closed",
-                               G_CALLBACK (lid_is_closed_changed), manager, 0);
+      if (manager->up_client)
+        {
+          g_signal_connect_object (manager->up_client, "notify::lid-is-closed",
+                                   G_CALLBACK (lid_is_closed_changed), manager, 0);
+        }
     }
 
   g_signal_connect_object (manager, "notify::power-save-mode",