Add a output_created_signal on weston_compositor
diff --git a/src/compositor.h b/src/compositor.h
index 3b08f29..ce63fc2 100644
--- a/src/compositor.h
+++ b/src/compositor.h
@@ -313,6 +313,7 @@
 	struct wl_signal hide_input_panel_signal;
 
 	struct wl_signal seat_created_signal;
+	struct wl_signal output_created_signal;
 
 	struct wl_event_loop *input_loop;
 	struct wl_event_source *input_loop_source;