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

chrome/browser/resources/chromeos/chromevox/common/dom_util_test.unitjs

 // 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.
 
 // Include test fixture.
 GEN_INCLUDE(['../testing/chromevox_unittest_base.js']);
 
 /**
  * Test fixture.
  * @constructor
  * @extends {ChromeVoxUnitTestBase}
  */
 function CvoxDomUtilUnitTest() {}
 
 CvoxDomUtilUnitTest.prototype = {
   __proto__: ChromeVoxUnitTestBase.prototype,
 
   /** @override */
   closureModuleDeps: [
     'cvox.ChromeVox',
     'cvox.DescriptionUtil',
     'cvox.DomUtil',
-    'cvox.TestMsgs',
+    'TestMsgs',
   ],
 
   /** @override */
   setUp: function() {
-    cvox.ChromeVox.msgs = new cvox.TestMsgs();
+    Msgs = TestMsgs;
   },
 
   asText_: function(node) {
     var temp = document.createElement('div');
     temp.appendChild(node);
     return temp.innerHTML;
   },
 
   assertEqualsAsText_: function(node1, node2) {
     assertEquals(this.asText_(node1), this.asText_(node2));
@@ skipping 1530 matching lines @@
   cvox.Memoize.scope(function() {
     container.style.visibility = 'hidden';
     assertFalse(cvox.DomUtil.isVisible(target));
 
     container.style.visibility = 'visible';
     // This should be true! It will return the wrong answer because
     // we're deliberately leaving memoization on while modifying the DOM.
     assertFalse(cvox.DomUtil.isVisible(target));
   });
 });