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pkg/web_components/test/interop_test.dart

Index: pkg/web_components/test/interop_test.dart
diff --git a/pkg/web_components/test/interop_test.dart b/pkg/web_components/test/interop_test.dart
index 89b297152469e370a62239915d57b58bc2c7acf3..c78a8abff76be7b7a99a8ac8a2cb547bd0e20afd 100644
--- a/pkg/web_components/test/interop_test.dart
+++ b/pkg/web_components/test/interop_test.dart
@@ -10,6 +10,7 @@ import 'dart:js' show context, JsObject;
 import 'package:unittest/html_config.dart';
 import 'package:unittest/unittest.dart';
 import 'package:web_components/interop.dart';
+import 'package:web_components/polyfill.dart';
 
 main() {
   useHtmlConfiguration();
@@ -17,6 +18,8 @@ main() {
   registerDartType('x-b', XBWrapper, extendsTag: 'div');
   registerDartType('x-c', XCWrapper);
 
+  setUp(() => customElementsReady);
+
   test('interop is supported', () {
     expect(isSupported, isTrue);
   });