Refactor: Extract a KeyboardHandler and CommandHandler from Background

chrome/browser/resources/chromeos/chromevox/cvox2/background/background_test.extjs

 // 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_next_e2e_test_base.js',
              '../../testing/assert_additions.js']);
 
 GEN_INCLUDE(['../../testing/mock_feedback.js']);
 
@@ skipping 29 matching lines @@
     return mockFeedback;
   },
 
   /**
    * Create a function which perform the command |cmd|.
    * @param {string} cmd
    * @return {function() : void}
    */
   doCmd: function(cmd) {
     return function() {
-      ChromeVoxState.instance.onGotCommand(cmd);
+      CommandHandler.onCommand(cmd);
     };
   },
 
   linksAndHeadingsDoc: function() {/*!
     <p>start</p>
     <a href='#a'>alpha</a>
     <a href='#b'>beta</a>
     <p>
       <h1>charlie</h1>
       <a href='foo'>delta</a>
@@ skipping 369 matching lines @@
           .expectSpeech(/slider/)
           .expectEarcon(cvox.Earcon.SLIDER);
 
       mockFeedback.replay();
     }.bind(this));
 });
 
 TEST_F('BackgroundTest', 'ToggleChromeVoxVersion', function() {
   var mockFeedback = this.createMockFeedback();
   this.runWithLoadedTree(this.linksAndHeadingsDoc, function() {
-    var gotCmd = ChromeVoxState.instance.onGotCommand;
+    var gotCmd = CommandHandler.onCommand;
 
     // The command came from the background keyboard handler.
     var togglerFromBackground = gotCmd.bind(gotCmd, 'toggleChromeVoxVersion');
 
     // The command came from a content script.
     var togglerFromContent = gotCmd.bind(gotCmd, 'toggleChromeVoxVersion',
                                          true);
 
     mockFeedback.call(togglerFromBackground)
         .expectSpeech('Switched to Classic ChromeVox')   
@@ skipping 124 matching lines @@
 
     assertEquals('iframe', iframe.role);
     assertEquals('button', button.role);
 
     var didFocus = false;
     iframe.focus = function() {
       didFocus = true;
     };
     var b = ChromeVoxState.instance;
     b.currentRange_ = cursors.Range.fromNode(button);
-    b.onGotCommand('previousElement');
+    doCmd('previousElement');
     assertFalse(didFocus);
   }.bind(this));
 });
 
 TEST_F('BackgroundTest', 'NoisySlider', function() {
   var mockFeedback = this.createMockFeedback();
   this.runWithLoadedTree(  function() {/*!
     <button id="go">go</button>
     <div id="slider" tabindex=0 role="slider"></div>
     <script>
@@ skipping 166 matching lines @@
 });
 
 TEST_F('BackgroundTest', 'ToggleButton', function() {
   var mockFeedback = this.createMockFeedback();
   this.runWithLoadedTree(function() {/*!
     <div aria-pressed="true" role="button">ok</div>
     <div aria-pressed="false" role="button">cancel</div>
     <div aria-pressed role="button">close</div>
   */}, function(root) {
     var b = ChromeVoxState.instance;
-    var move = b.onGotCommand.bind(b, 'nextObject');
+    var move = doCmd('nextObject');
     mockFeedback.call(move)
         .expectSpeech('ok')
         .expectSpeech('Button')
         .expectSpeech('Pressed')
 
         .call(move)
         .expectSpeech('cancel')
         .expectSpeech('Button')
         .expectSpeech('Not pressed')
 
@@ skipping 187 matching lines @@
 
 TEST_F('BackgroundTest', 'Selection', function() {
   var mockFeedback = this.createMockFeedback();
   this.runWithLoadedTree(function(root) {/*!
     <p>simple</p>
     <p>doc</p>
   */}, function(root) {
     // Fakes a toggleSelection command.
     root.addEventListener('textSelectionChanged', function() {
       if (root.focusOffset == 3)
-        ChromeVoxState.instance.onGotCommand('toggleSelection');
+        CommandHandler.onCommand('toggleSelection');
     }, true);
 
     mockFeedback.call(doCmd('toggleSelection'))
         .expectSpeech('simple', 'selected')
         .call(doCmd('nextCharacter'))
         .expectSpeech('i', 'selected')
         .call(doCmd('previousCharacter'))
         .expectSpeech('i', 'unselected')
         .call(doCmd('nextCharacter'))
         .call(doCmd('nextCharacter'))
         .expectSpeech('End selection', 'sim')
         .replay();
   });
 });