Ensure WebView notifies desktop automation on creation, destruction, and change

chrome/browser/resources/chromeos/chromevox/cvox2/background/output.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 Provides output services for ChromeVox.
  */
 
 goog.provide('Output');
 goog.provide('Output.EventType');
 
 goog.require('AutomationUtil.Dir');
 goog.require('cursors.Cursor');
 goog.require('cursors.Range');
 goog.require('cursors.Unit');
+goog.require('cvox.AbstractEarcons');
+goog.require('cvox.NavBraille');
 goog.require('cvox.Spannable');
 goog.require('cvox.ValueSelectionSpan');
 goog.require('cvox.ValueSpan');
 
 goog.scope(function() {
 var Dir = AutomationUtil.Dir;
 
 /**
  * An Output object formats a cursors.Range into speech, braille, or both
  * representations. This is typically a cvox.Spannable.
@@ skipping 680 matching lines @@
     }
 
     if (currentNode != root)
       throw 'Unbalanced parenthesis.';
 
     return root;
   }
 };
 
 });  // goog.scope