Add tests for webRequest events and frame unload

chrome/test/data/extensions/api_test/webrequest/unload/load_frame.js

Index: chrome/test/data/extensions/api_test/webrequest/unload/load_frame.js
diff --git a/chrome/test/data/extensions/api_test/webrequest/unload/load_frame.js b/chrome/test/data/extensions/api_test/webrequest/unload/load_frame.js
new file mode 100644
index 0000000000000000000000000000000000000000..048425df099077116b51dabd07f428e36f496b92
--- /dev/null
+++ b/chrome/test/data/extensions/api_test/webrequest/unload/load_frame.js
@@ -0,0 +1,12 @@
+// Copyright 2016 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.
+
+var frameUrl = decodeURIComponent(location.search.slice(1));
+console.assert(frameUrl, 'Frame URL must be specified after "?".');
+
+window.onload = function() {
+  var f = document.createElement('iframe');
+  f.src = frameUrl;
+  document.body.appendChild(f);
+};