Expose the notificationclick and notificationerror events on ServiceWorkerGlobalScope

LayoutTests/http/tests/notifications/resources/serviceworker-notification-event.js

Index: LayoutTests/http/tests/notifications/resources/serviceworker-notification-event.js
diff --git a/LayoutTests/http/tests/notifications/resources/serviceworker-notification-event.js b/LayoutTests/http/tests/notifications/resources/serviceworker-notification-event.js
index 9d26a66d64e7c830dee99992aec33d7a2cf32804..55d8e2226663d49aba54a4192672287ff55dcd61 100644
--- a/LayoutTests/http/tests/notifications/resources/serviceworker-notification-event.js
+++ b/LayoutTests/http/tests/notifications/resources/serviceworker-notification-event.js
@@ -5,3 +5,9 @@ test(function() {
     assert_true('NotificationEvent' in self);
 
 }, 'NotificationEvent is exposed.');
+
+test(function() {
+    assert_own_property(self, 'onnotificationclick', 'The notificationclick event exists.');
+    assert_own_property(self, 'onnotificationerror', 'The notificationerror event exists.');
+
+}, 'The notificationclick and notificationerror events exist on the global scope.');