[extension SW] Support lazy events from extension service workers.

content/public/test/service_worker_test_helpers.h

Index: content/public/test/service_worker_test_helpers.h
diff --git a/content/public/test/service_worker_test_helpers.h b/content/public/test/service_worker_test_helpers.h
new file mode 100644
index 0000000000000000000000000000000000000000..786c5d3ae786238841b0a0c41d0da8fda7e638cb
--- /dev/null
+++ b/content/public/test/service_worker_test_helpers.h
@@ -0,0 +1,25 @@
+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_PUBLIC_TEST_SERVICE_WORKER_TEST_OBSERVER_H_
+#define CONTENT_PUBLIC_TEST_SERVICE_WORKER_TEST_OBSERVER_H_
+
+#include "base/callback_forward.h"
+
+class GURL;
+namespace content {
+
+class ServiceWorkerContext;
+
+// Stops a running service worker at origin |origin|, and calls
+// |complete_callback_ui| callback on UI thread when done.
+//
+// Can be called from UI/IO thread.
+void StopServiceWorkerAtOrigin(ServiceWorkerContext* context,
+                               const GURL& origin,
+                               base::OnceClosure complete_callback_ui);
+
+}  // namespace content
+
+#endif  // CONTENT_PUBLIC_TEST_SERVICE_WORKER_TEST_OBSERVER_H_