Stop Service Workers that execute JavaScript for too long.

content/test/data/service_worker/while_true_worker.js

Index: content/test/data/service_worker/while_true_worker.js
diff --git a/chrome/test/data/ssl/write_to_title.js b/content/test/data/service_worker/while_true_worker.js
similarity index 79%
copy from chrome/test/data/ssl/write_to_title.js
copy to content/test/data/service_worker/while_true_worker.js
index 747eb604156d99ab8c8b638a0085ce3152af4a94..ebfc2249c9bb157d0f29eb3da12130efb4858ed2 100644
--- a/chrome/test/data/ssl/write_to_title.js
+++ b/content/test/data/service_worker/while_true_worker.js
@@ -1,4 +1,5 @@
 // Copyright 2015 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.
-document.title = "This script has loaded";
+
+while(true) { }