Switch to selected 8-dot braille table in email and url text fields

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

 // Copyright 2015 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 An interface for querying and modifying the global
  *     ChromeVox state, to avoid direct dependencies on the Background
  *     object and to facilitate mocking for tests.
  */
 
 goog.provide('ChromeVoxMode');
 goog.provide('ChromeVoxState');
+goog.provide('ChromeVoxStateObserver');
 
 goog.require('cursors.Cursor');
+goog.require('cursors.Range');
 
 /**
  * All possible modes ChromeVox can run.
  * @enum {string}
  */
 ChromeVoxMode = {
   CLASSIC: 'classic',
   CLASSIC_COMPAT: 'classic_compat',
   NEXT: 'next',
   FORCE_NEXT: 'force_next'
 };
 
 /**
+ * An interface implemented by objects that want to observe ChromeVox state
+ * changes.
+ * @interface
+ */
+ChromeVoxStateObserver = function() {};
+
+ChromeVoxStateObserver.prototype = {
+  /**
+   * @param {cursors.Range} range The new range.
+   */
+  onCurrentRangeChanged: function(range) {}
+};
+
+/**
  * ChromeVox2 state object.
  * @constructor
  */
 ChromeVoxState = function() {
   if (ChromeVoxState.instance)
     throw 'Trying to create two instances of singleton ChromeVoxState.';
   ChromeVoxState.instance = this;
 };
 
 /**
@@ skipping 35 matching lines @@
    * @return {cursors.Range} The current range.
    * @protected
    */
   getCurrentRange: function() {
     return null;
   },
 
   /**
    * @param {cursors.Range} newRange The new range.
    */
-  setCurrentRange: goog.abstractMethod,
+  setCurrentRange: goog.abstractMethod
 };
+
+/** @type {!Array<ChromeVoxStateObserver>} */
+ChromeVoxState.observers = [];
+
+/**
+ * @param {ChromeVoxStateObserver} observer
+ */
+ChromeVoxState.addObserver = function(observer) {
+  this.observers.push(observer);
+};