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

chrome/browser/resources/chromeos/chromevox/walkers/walker_unittest_base.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.
 
 GEN_INCLUDE(['../testing/chromevox_unittest_base.js']);
 
 /**
  * Base class for walker test fixtures.
  * @constructor
  * @extends {ChromeVoxUnitTestBase}
  */
 function CvoxWalkerUnitTestBase() {}
 
 CvoxWalkerUnitTestBase.prototype = {
   __proto__: ChromeVoxUnitTestBase.prototype,
 
   /** @override */
   closureModuleDeps: [
-    'cvox.CursorSelection',
-    'cvox.TestMsgs'
+    'TestMsgs',
+    'cvox.CursorSelection'
   ],
 
   /**
    * Common set up for all walker test cases.
    */
   setUp: function() {
     // Needed for getDescription and getGranularityMsg.
-    cvox.ChromeVox.msgs = new cvox.TestMsgs();
+    Msgs = TestMsgs;
 
     // Delete all nodes in the body.
     while (document.body.hasChildNodes()) {
       document.body.removeChild(document.body.lastChild);
     }
 
     this.walker = this.newWalker();
   },
 
   /**
@@ skipping 186 matching lines @@
    */
   TEST_F(testFixture, 'testEmptyBody', function() {
     var sel = cvox.CursorSelection.fromBody();
 
     // Testing for infinite loop. If one exists, this test will fail by timing
     // out.
     var sync = this.walker.sync(sel);
     var next = this.walker.next(sel);
   });
 };