[Test] Added a test for activeTab URL filtering

chrome/test/data/extensions/api_test/active_tab/background.js

 // Copyright (c) 2012 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 assertEq = chrome.test.assertEq;
 var assertFalse = chrome.test.assertFalse;
 var assertTrue = chrome.test.assertTrue;
 var callbackFail = chrome.test.callbackFail;
 var callbackPass = chrome.test.callbackPass;
 
@@ skipping 24 matching lines @@
     iframeDone();
   }
 });
 
 var iframeUrl = chrome.extension.getURL('iframe.html');
 var injectIframe =
     'var iframe = document.createElement("iframe");\n' +
     'iframe.src = "' + iframeUrl + '";\n' +
     'document.body.appendChild(iframe);\n';
 
+var runCount = 0;
+
 chrome.browserAction.onClicked.addListener(function(tab) {
+  runCount++;
+  if (runCount == 1) {

[Devlin, 2017/05/23 20:49:21]

add some comments explaining the ordering here.

[Ivan Šandrk, 2017/05/24 16:36:51]

Done.

+    assertTrue(tab.url == undefined);

[Devlin, 2017/05/23 20:49:21]

maybe just: assertFalse(!!tab.url);

[Ivan Šandrk, 2017/05/24 16:36:51]

Done.

+    return chrome.test.succeed();

[Devlin, 2017/05/23 20:49:21]

chrome.test.succeed() doesn't return anything, so prefer:
chrome.test.succeed();
return;

[Ivan Šandrk, 2017/05/24 16:36:51]

Done.

+  } else if (runCount == 3) {
+    chrome.test.sendMessage(tab.url);
+    return chrome.test.succeed();
+  }
+
   iframeDone = chrome.test.callbackAdded();
   cachedUrl = tab.url;
   chrome.tabs.executeScript({ code: injectIframe }, callbackPass());
   assertTrue(canXhr(tab.url));
 
   chrome.automation.getTree(callbackPass(function(rootNode) {
     assertFalse(rootNode == undefined);
     assertEq(RoleType.ROOT_WEB_AREA, rootNode.role);
   }));
 });
 
 chrome.webNavigation.onCompleted.addListener(function(details) {
   chrome.tabs.executeScript({ code: 'true' }, callbackFail(
          'Cannot access contents of the page. ' +
          'Extension manifest must request permission to access the ' +
          'respective host.'));
 
   chrome.automation.getTree(callbackFail(
       'Cannot request automation tree on url "' + details.url +
         '". Extension manifest must request permission to access this host.'));
 
   assertFalse(canXhr(details.url));
 });