diff --git a/lib/web_ui/test/engine/assets_test.dart b/lib/web_ui/test/engine/assets_test.dart
index 9c6993b5d510f..cdf5459ca2c43 100644
--- a/lib/web_ui/test/engine/assets_test.dart
+++ b/lib/web_ui/test/engine/assets_test.dart
@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 @TestOn('browser')
+library;
 
 import 'package:test/bootstrap/browser.dart';
 import 'package:test/test.dart';