Reland of Accessibility: Ignore all anonymous blocks

chrome/test/data/extensions/api_test/automation/tests/tabs/location.js

 // Copyright 2014 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 allTests = [
   function testLocation() {
     function assertOkButtonLocation(event) {
-      var okButton = rootNode.firstChild.firstChild;
+      var okButton = rootNode.find({ role: RoleType.button,
+                                     attributes: { name: 'Ok' }});
       assertTrue('location' in okButton);
 
       // We can't assert the left and top positions because they're
       // returned in global screen coordinates. Just check the width and
       // height.
       assertEq(300, okButton.location.width);
       assertEq(400, okButton.location.height);
       chrome.test.succeed();
     };
 
     var okButton = rootNode.firstChild.firstChild;
     assertTrue('location' in okButton, 'no location in okButton');
     assertTrue('left' in okButton.location, 'no left in location');
     assertTrue('top' in okButton.location, 'no top in location');
     assertTrue('height' in okButton.location, 'no height in location');
     assertTrue('width' in okButton.location, 'no width in location');
 
     rootNode.addEventListener(
         EventType.childrenChanged, assertOkButtonLocation);
     chrome.tabs.executeScript({ 'code':
           'document.querySelector("button")' +
           '.setAttribute("style", "position: absolute; left: 100; top: 200; ' +
           'width: 300; height: 400;");' });
   }
 ];
 
 setUpAndRunTests(allTests);