Ensure fake alert window attached to AXAura tree and refine alert dialog output

chrome/browser/resources/chromeos/chromevox/cvox2/background/automation_predicate.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.
 
 /**
  * @fileoverview ChromeVox predicates for the automation extension API.
  */
 
 goog.provide('AutomationPredicate');
 goog.provide('AutomationPredicate.Binary');
@@ skipping 282 matching lines @@
   })(node);
 };
 
 /**
  * Matches against nodes that contain interesting nodes, but should never be
  * visited.
  * @param {!AutomationNode} node
  * @return {boolean}
  */
 AutomationPredicate.structuralContainer = AutomationPredicate.roles([
+    Role.alertDialog,
+    Role.dialog,
     Role.rootWebArea,
     Role.webView,
+    Role.window,
     Role.embeddedObject,
     Role.iframe,
     Role.iframePresentational]);
 
 /**
  * Returns whether the given node should not be crossed when performing
  * traversals up the ancestry chain.
  * @param {AutomationNode} node
  * @return {boolean}
  */
@@ skipping 37 matching lines @@
 
   // Ignore some roles.
   return AutomationPredicate.leaf(node) &&
       (AutomationPredicate.roles([Role.client,
                                   Role.column,
                                   Role.div,
                                   Role.group,
                                   Role.image,
                                   Role.staticText,
                                   Role.svgRoot,
-                                  Role.tableHeaderContainer])(node));
+                                  Role.tableHeaderContainer,
+                                  Role.unknown
+                                 ])(node));
 };
 
 /**
  * Returns if the node has a meaningful checked state.
  * @param {!AutomationNode} node
  * @return {boolean}
  */
 AutomationPredicate.checkable = AutomationPredicate.roles([
   Role.checkBox,
   Role.radioButton,
@@ skipping 88 matching lines @@
  * @param {number} level 1-6
  * @return {AutomationPredicate.Unary}
  */
 AutomationPredicate.makeHeadingPredicate = function(level) {
   return function(node) {
     return node.role == Role.heading && node.hierarchicalLevel == level;
   };
 };
 
 });  // goog.scope