Improve <adview> implementation and add tests.

chrome/test/data/extensions/platform_apps/ad_view/invalid_ad_network/chrometest.js

Index: chrome/test/data/extensions/platform_apps/ad_view/invalid_ad_network/chrometest.js
diff --git a/chrome/test/data/extensions/platform_apps/ad_view/invalid_ad_network/chrometest.js b/chrome/test/data/extensions/platform_apps/ad_view/invalid_ad_network/chrometest.js
new file mode 100644
index 0000000000000000000000000000000000000000..ff47a74c4cb6128a3a3ec701d2f59a5161400599
--- /dev/null
+++ b/chrome/test/data/extensions/platform_apps/ad_view/invalid_ad_network/chrometest.js
@@ -0,0 +1,81 @@
+// 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.
+
+var adview1 = "adview1";
+var adview2 = "adview2";
+var adview3 = "adview3";
+
+
+/**
+ * Verify setting invalid ad-network value is ignored in immediate Javascript
+ * code (i.e. before document is fully loaded) on a static <adview> element.
+ */
+function runTest1() {
+  // Arrange
+  var adview = document.getElementById(adview1);
+
+  // Act
+  adview.setAttribute("ad-network", "invalidAdNetwork");
+
+  // Assert
+  // Note: The assertion has to happen in a callback function because of the
+  //  way mutation observer events are processed. See
+  //  http://lists.w3.org/Archives/Public/public-webapps/2011JulSep/1622.html
+  setTimeout(function() {
+    chrome.test.assertEq("", adview.getAttribute("ad-network"));
+  }, 0);
+}
+
+/**
+ * Verify setting invalid ad-network value is ignored at "document load" time.
+ */
+function runTest2() {
+  // Arrange
+  var adview = document.createElement("adview");
+  adview.id = adview2;
+  document.body.appendChild(adview);
+
+  // Act
+  adview.setAttribute("ad-network", "invalidAdNetwork2");
+
+  // Assert
+  // Note: The assertion has to happen in a callback function because of the
+  //  way mutation observer events are processed. See
+  //  http://lists.w3.org/Archives/Public/public-webapps/2011JulSep/1622.html
+  setTimeout(function() {
+    chrome.test.assertEq("", adview.getAttribute("ad-network"));
+  }, 0);
+}
+
+/**
+ * Verify setting invalid ad-network value is ignored even after document
+ * is fully loaded.
+ */
+function runTest3() {
+  setTimeout(function() {
+    // Arrange
+    var adview = document.createElement("adview");
+    adview.id = adview3;
+    document.body.appendChild(adview);
+
+    // Act
+    adview.setAttribute("ad-network", "invalidAdNetwork3");
+
+    // Assert
+    // Note: The assertion has to happen in a callback function because of the
+    //  way mutation observer events are processed. See
+    //  http://lists.w3.org/Archives/Public/public-webapps/2011JulSep/1622.html
+    setTimeout(function() {
+      chrome.test.assertEq("", adview.getAttribute("ad-network"));
+      chrome.test.sendMessage("test-finished");
+    }, 0);
+  }, 0);
+}
+
+runTest1();
+
+window.addEventListener('DOMContentLoaded', function() {
+  runTest2();
+  runTest3();
+});