Improve braille related message descriptions and clean up message handling in Chromevox.

chrome/browser/resources/chromeos/chromevox/common/node_state.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 The cvox.NodeState typedef.
  */
 
 goog.provide('cvox.NodeState');
 goog.provide('cvox.NodeStateUtil');
 
+goog.require('Msgs');
+
 /**
  * Holds the state of a node.  It is an Array or Arrays of strings and numbers.
  * Each sub array is in the format:
  * [state, opt_arg, opt_arg, ...].  These sub arrays map directly to a
  * cvox.ChromeVox.getMsg() call. For example [list_position, 3, 5] maps to
  * getMsg('list_position', [3, 5]);
  *
  * @typedef {!Array<!Array<string|number>>}
  */
 cvox.NodeState;
 
 /**
  * Returns a localized, readable string with the NodeState.
  *
  * NOTE(deboer): Once AriaUtil and DomUtil are using NodeState exclusively, this
  * function can be moved into DescriptionUtil, removing the cvox.ChromeVox
  * dependency here.
  *
  * @param {cvox.NodeState} state The node state.
  * @return {string} The readable state string.
  */
 cvox.NodeStateUtil.expand = function(state) {
   try {
     return state.map(function(s) {
       if (s.length < 1) {
         throw new Error('cvox.NodeState must have at least one entry');
       }
       var args = s.slice(1).map(function(a) {
         if (typeof a == 'number') {
-          return cvox.ChromeVox.msgs.getNumber(a);
+          return Msgs.getNumber(a);
         }
         return a;
       });
-      return cvox.ChromeVox.msgs.getMsg(/** @type {string} */ (s[0]), args);
+      return Msgs.getMsg(/** @type {string} */ (s[0]), args);
     }).join(' ');
   } catch (e) {
     throw new Error('error: ' + e + ' state: ' + state);
   }
 };