gizmo: Set the name

This helps with debugging.

gtk/gtkgizmo.c

diff --git a/gtk/gtkgizmo.c b/gtk/gtkgizmo.c
index a3ef5d1..f8c6f5c 100644
--- a/gtk/gtkgizmo.c
+++ b/gtk/gtkgizmo.c
@@ -107,6 +107,7 @@
 {
   GtkGizmo *gizmo = GTK_GIZMO (g_object_new (GTK_TYPE_GIZMO,
                                              "css-name", css_name,
+                                             "name", css_name,
                                              NULL));
 
   gizmo->measure_func  = measure_func;