backends: Centralize panel autorotation in a DisplayConfig property

Instead of having everyone check net.hadess.SensorProxy themselves, have
this all controlled by the MetaOrientationManager, and proxied everywhere
else via a readonly property in org.gnome.Mutter.DisplayConfig.

We want to attach more complex policies here, and it seems better to
centralize the handling of the autorotation feature rather than
implementing policy changes all over the place.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1311

src/backends/meta-monitor-manager-private.h

@@ -129,6 +129,8 @@ struct _MetaMonitorManager
 
   int persistent_timeout_id;
 
+  guint panel_orientation_managed : 1;
+
   MetaMonitorConfigManager *config_manager;
 
   GnomePnpIds *pnp_ids;

src/backends/meta-monitor-manager.c

@@ -67,6 +67,7 @@ enum
   PROP_0,
 
   PROP_BACKEND,
+  PROP_PANEL_ORIENTATION_MANAGED,
 
   PROP_LAST
 };
@@ -748,6 +749,28 @@ experimental_features_changed (MetaSettings           *settings,
   meta_settings_update_ui_scaling_factor (settings);
 }
 
+static void
+update_panel_orientation_managed (MetaMonitorManager *manager)
+{
+  MetaOrientationManager *orientation_manager;
+  gboolean panel_orientation_managed;
+
+  orientation_manager = meta_backend_get_orientation_manager (manager->backend);
+
+  panel_orientation_managed =
+    meta_orientation_manager_has_accelerometer (orientation_manager);
+
+  if (manager->panel_orientation_managed == panel_orientation_managed)
+    return;
+
+  manager->panel_orientation_managed = panel_orientation_managed;
+  g_object_notify_by_pspec (G_OBJECT (manager),
+                            obj_props[PROP_PANEL_ORIENTATION_MANAGED]);
+
+  meta_dbus_display_config_set_panel_orientation_managed (manager->display_config,
+                                                          manager->panel_orientation_managed);
+}
+
 void
 meta_monitor_manager_setup (MetaMonitorManager *manager)
 {
@@ -788,6 +811,11 @@ meta_monitor_manager_constructed (GObject *object)
                            G_CALLBACK (orientation_changed),
                            manager, 0);
 
+  g_signal_connect_object (meta_backend_get_orientation_manager (backend),
+                           "notify::has-accelerometer",
+                           G_CALLBACK (update_panel_orientation_managed), manager,
+                           G_CONNECT_SWAPPED);
+
   g_signal_connect_object (backend,
                            "lid-is-closed-changed",
                            G_CALLBACK (lid_is_closed_changed),
@@ -848,6 +876,7 @@ meta_monitor_manager_set_property (GObject      *object,
     case PROP_BACKEND:
       manager->backend = g_value_get_object (value);
       break;
+    case PROP_PANEL_ORIENTATION_MANAGED:
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
     }
@@ -866,6 +895,9 @@ meta_monitor_manager_get_property (GObject    *object,
     case PROP_BACKEND:
       g_value_set_object (value, manager->backend);
       break;
+    case PROP_PANEL_ORIENTATION_MANAGED:
+      g_value_set_boolean (value, manager->panel_orientation_managed);
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
     }
@@ -925,6 +957,15 @@ meta_monitor_manager_class_init (MetaMonitorManagerClass *klass)
                          G_PARAM_READWRITE |
                          G_PARAM_CONSTRUCT_ONLY |
                          G_PARAM_STATIC_STRINGS);
+
+  obj_props[PROP_PANEL_ORIENTATION_MANAGED] =
+    g_param_spec_boolean ("panel-orientation-managed",
+                          "Panel orientation managed",
+                          "Panel orientation is managed",
+                          FALSE,
+                          G_PARAM_READABLE |
+                          G_PARAM_EXPLICIT_NOTIFY |
+                          G_PARAM_STATIC_STRINGS);
   g_object_class_install_properties (object_class, PROP_LAST, obj_props);
 }
 
@@ -3175,3 +3216,11 @@ meta_monitor_manager_get_vendor_name (MetaMonitorManager *manager,
 
   return gnome_pnp_ids_get_pnp_id (manager->pnp_ids, vendor);
 }
+
+gboolean
+meta_monitor_manager_get_panel_orientation_managed (MetaMonitorManager *manager)
+{
+  g_return_val_if_fail (META_IS_MONITOR_MANAGER (manager), FALSE);
+
+  return manager->panel_orientation_managed;
+}

src/meta/meta-monitor-manager.h

@@ -62,4 +62,7 @@ MetaMonitorSwitchConfigType meta_monitor_manager_get_switch_config (MetaMonitorM
 META_EXPORT
 gint meta_monitor_manager_get_display_configuration_timeout (void);
 
+META_EXPORT
+gboolean meta_monitor_manager_get_panel_orientation_managed (MetaMonitorManager *manager);
+
 #endif /* META_MONITOR_MANAGER_H */

src/org.gnome.Mutter.DisplayConfig.xml

@@ -282,6 +282,14 @@
     -->
     <property name="PowerSaveMode" type="i" access="readwrite" />
 
+    <!--
+        PanelOrientationManaged:
+
+        Whether the built-in panel orientation is automatically managed
+        by mutter.
+    -->
+    <property name="PanelOrientationManaged" type="b" access="read" />
+
     <!--
         MonitorsChanged: