Enable <adview> tag for packaged apps.

chrome/test/data/extensions/platform_apps/ad_view/load_event/main.js

+// Copyright (c) 2013 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.
+
+/**
+ * Listens for the app launching then creates the window
+ *
+ * @see http://developer.chrome.com/trunk/apps/app.runtime.html
+ * @see http://developer.chrome.com/trunk/apps/app.window.html
+ */
+chrome.app.runtime.onLaunched.addListener(function() {
+  chrome.app.window.create('index.html',
+                           {top:0, left: 0,  width: 900, height: 800});
+});