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

chrome/browser/resources/chromeos/chromevox/cvox2/background/automation_predicate.js

Index: chrome/browser/resources/chromeos/chromevox/cvox2/background/automation_predicate.js
diff --git a/chrome/browser/resources/chromeos/chromevox/cvox2/background/automation_predicate.js b/chrome/browser/resources/chromeos/chromevox/cvox2/background/automation_predicate.js
index dfbd273d00c9ef9563fdb30dfbcebf2fffd4e319..098ea678ecf0dad4f5d8af0fb73e2b58b115dcef 100644
--- a/chrome/browser/resources/chromeos/chromevox/cvox2/background/automation_predicate.js
+++ b/chrome/browser/resources/chromeos/chromevox/cvox2/background/automation_predicate.js
@@ -300,8 +300,11 @@ AutomationPredicate.container = function(node) {
  * @return {boolean}
  */
 AutomationPredicate.structuralContainer = AutomationPredicate.roles([
+    Role.alertDialog,
+    Role.dialog,
     Role.rootWebArea,
     Role.webView,
+    Role.window,
     Role.embeddedObject,
     Role.iframe,
     Role.iframePresentational]);
@@ -359,7 +362,9 @@ AutomationPredicate.shouldIgnoreNode = function(node) {
                                   Role.image,
                                   Role.staticText,
                                   Role.svgRoot,
-                                  Role.tableHeaderContainer])(node));
+                                  Role.tableHeaderContainer,
+                                  Role.unknown
+                                 ])(node));
 };
 
 /**