toytoolkit: Don't segfault on window close

Without this commit, the client will segmentation fault due to accessing
the frame after everything has been destroyed.
diff --git a/clients/window.c b/clients/window.c
index e9acacf..dd6a213 100644
--- a/clients/window.c
+++ b/clients/window.c
@@ -2396,7 +2396,7 @@
 					      window->user_data);
 		else
 			display_exit(window->display);
-		frame_status_clear(frame->frame, FRAME_STATUS_CLOSE);
+		return;
 	}
 
 	if ((status & FRAME_STATUS_MOVE) && window->shell_surface) {