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

chrome/browser/resources/chromeos/chromevox/common/aria_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 for aria_util.js.
  * @constructor
@@ skipping 14 matching lines @@
 TEST_F('CvoxAriaUtilUnitTest', 'GetStateGridWithActiveCell', function() {
   this.loadDoc(function() {/*!
     <div id="grid" role="grid" aria-activedescendant="cell">
       <div role="row">
         <div id="cell" role="gridcell">
       </div>
     </div>
   */});
   assertThat(
       cvox.AriaUtil.getStateMsgs($('grid'), true),
-      eqJSON([['aria_role_gridcell_pos', 1, 1]]));
+      eqJSON([['role_gridcell_pos', 1, 1]]));
 });
 
 TEST_F('CvoxAriaUtilUnitTest', 'GetActiveDescendant', function() {
   this.loadDoc(function() {/*!
     <div id="top" aria-activedescendant="child">
       <div id="child" />
     </div>
     <div id="top_2" aria-activedescendant="child_2">
       <div id="child_2" aria-activedescendant="grandchild_2">
         <div id="grandchild_2" />
@@ skipping 87 matching lines @@
   var outerLiveRegions = cvox.AriaUtil.getLiveRegions(outer);
   assertEquals(2, outerLiveRegions.length);
   assertNotEquals(-1, outerLiveRegions.indexOf(progress));
   assertNotEquals(-1, outerLiveRegions.indexOf(progress2));
 
   // getLiveRegions works walking up the tree as well.
   var ptextLiveRegions = cvox.AriaUtil.getLiveRegions(ptext);
   assertEquals(1, ptextLiveRegions.length);
   assertNotEquals(-1, ptextLiveRegions.indexOf(progress));
 });