policy: track the exported session instead of the proxy

The proxy takes more roundtrips to get updated and this makes the
policy fail to find a default endpoint at startup, right after
the devices have been discovered

This also removes the weak ref on the session, since the object
manager internally maintains a reference on the objects that
it manages.

lib/wp/policy.c

@@ -19,7 +19,6 @@ struct _WpPolicyManager
   GList *policies;
   WpObjectManager *endpoints_om;
   WpObjectManager *sessions_om;
-  GWeakRef curr_session;
 };
 
 enum {
@@ -36,7 +35,6 @@ wp_policy_manager_init (WpPolicyManager *self)
 {
   self->endpoints_om = wp_object_manager_new ();
   self->sessions_om = wp_object_manager_new ();
-  g_weak_ref_init (&self->curr_session, NULL);
 }
 
 static void
@@ -46,7 +44,6 @@ wp_policy_manager_finalize (GObject *object)
 
   g_debug ("WpPolicyManager destroyed");
 
-  g_weak_ref_clear (&self->curr_session);
   g_clear_object (&self->sessions_om);
   g_clear_object (&self->endpoints_om);
   g_list_free_full (self->policies, g_object_unref);
@@ -96,16 +93,6 @@ policy_mgr_endpoint_removed (WpObjectManager *om, WpBaseEndpoint *ep,
   }
 }
 
-static void
-policy_mgr_session_changed (WpObjectManager *om, WpPolicyManager *self)
-{
-  g_autoptr (GPtrArray) arr = NULL;
-
-  arr = wp_object_manager_get_objects (om, WP_TYPE_PROXY_SESSION);
-  if (arr->len > 0)
-    g_weak_ref_set (&self->curr_session, g_ptr_array_index (arr, 0));
-}
-
 /**
  * wp_policy_manager_get_instance:
  * @core: the #WpCore
@@ -135,11 +122,8 @@ wp_policy_manager_get_instance (WpCore *core)
     wp_core_install_object_manager (core, mgr->endpoints_om);
 
     /* install the object manager to listen to changed sessions */
-    wp_object_manager_add_proxy_interest (mgr->sessions_om,
-        PW_TYPE_INTERFACE_Session, NULL,
-        WP_PROXY_FEATURE_INFO | WP_PROXY_SESSION_FEATURE_DEFAULT_ENDPOINT);
-    g_signal_connect_object (mgr->sessions_om, "objects-changed",
-        (GCallback) policy_mgr_session_changed, mgr, 0);
+    wp_object_manager_add_object_interest (mgr->sessions_om,
+        WP_TYPE_EXPORTED_SESSION, NULL);
     wp_core_install_object_manager (core, mgr->sessions_om);
 
     wp_core_register_object (core, g_object_ref (mgr));
@@ -151,9 +135,12 @@ wp_policy_manager_get_instance (WpCore *core)
 WpSession *
 wp_policy_manager_get_session (WpPolicyManager *self)
 {
-  g_return_val_if_fail (self, NULL);
+  g_autoptr (GPtrArray) arr = NULL;
+
+  g_return_val_if_fail (WP_IS_POLICY_MANAGER (self), NULL);
 
-  return g_weak_ref_get (&self->curr_session);
+  arr = wp_object_manager_get_objects (self->sessions_om, 0);
+  return (arr->len > 0) ? g_object_ref (g_ptr_array_index (arr, 0)) : NULL;
 }
 
 static inline gboolean