[mutter/bilelmoussaoui/settings-daemon: 3/4] backend: Check if the gsettings scheme exists

[Bilal Elmoussaoui <bilelmoussaoui src gnome org>]

commit 14b0619f07adbc4f76fec153ada1aa51c7ada7b3
Author: Bilal Elmoussaoui <belmouss redhat com>
Date:   Tue May 3 12:40:13 2022 +0200

    backend: Check if the gsettings scheme exists
    
    Mutter makes use of a gsettings scheme that comes from
    gnome-settings-daemon to check for the screen orientation.
    In use cases where gnome-settings-daemon is not available,
    this would lead to a crash as the key doesn't exists

 src/backends/meta-orientation-manager.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)
---
diff --git a/src/backends/meta-orientation-manager.c b/src/backends/meta-orientation-manager.c
index 7989aa84fc..a7f55a32d2 100644
--- a/src/backends/meta-orientation-manager.c
+++ b/src/backends/meta-orientation-manager.c
@@ -273,6 +273,8 @@ iio_sensor_vanished_cb (GDBusConnection *connection,
 static void
 meta_orientation_manager_init (MetaOrientationManager *self)
 {
+
+  GSettingsSchemaSource *schema_source = g_settings_schema_source_get_default ();
   self->iio_watch_id = g_bus_watch_name (G_BUS_TYPE_SYSTEM,
                                          "net.hadess.SensorProxy",
                                          G_BUS_NAME_WATCHER_FLAGS_NONE,
@@ -281,10 +283,13 @@ meta_orientation_manager_init (MetaOrientationManager *self)
                                          self,
                                          NULL);
 
-  self->settings = g_settings_new (CONF_SCHEMA);
-  g_signal_connect_object (self->settings, "changed::"ORIENTATION_LOCK_KEY,
-                           G_CALLBACK (orientation_lock_changed), self, 0);
-  sync_state (self);
+  if (g_settings_schema_source_lookup (schema_source, CONF_SCHEMA, TRUE))
+    {
+      self->settings = g_settings_new (CONF_SCHEMA);
+      g_signal_connect_object (self->settings, "changed::"ORIENTATION_LOCK_KEY,
+                               G_CALLBACK (orientation_lock_changed), self, 0);
+      sync_state (self);
+    }
 }
 
 static void