Remove the use of KeyEvent.keyIdentifier.

ui/file_manager/file_manager/background/js/test_util.js

 // Copyright (c) 2013 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.
 
 /**
  * Opens the main Files.app's window and waits until it is ready.
  *
  * @param {Object} appState App state.
  * @param {function(string)} callback Completion callback with the new window's
  *     App ID.
@@ skipping 169 matching lines @@
  * @param {Window} contentWindow Window to be tested.
  * @param {string} filename Name of the file to be copied.
  * @return {boolean} True if copying got simulated successfully. It does not
  *     say if the file got copied, or not.
  */
 test.util.sync.copyFile = function(contentWindow, filename) {
   if (!test.util.sync.selectFile(contentWindow, filename))
     return false;
   // Ctrl+C and Ctrl+V
   test.util.sync.fakeKeyDown(
-      contentWindow, '#file-list', 'w', 'U+0043', true, false, false);
+      contentWindow, '#file-list', 'c', 'U+0043', true, false, false);

[oka, 2016/06/09 13:32:31]

Can you remove keyIdentifier from fakeKeyDown?

[fukino, 2016/06/09 13:47:50]

As the cr.ui.Command still depends on keyIdentifier property of the event
object, so we need it right now.
I'll remove it once we remove the dependency from cr.ui.Command.

   test.util.sync.fakeKeyDown(
       contentWindow, '#file-list', 'v', 'U+0056', true, false, false);
   return true;
 };
 
 /**
  * Selects |filename| and fakes pressing the Delete key.
  *
  * @param {Window} contentWindow Window to be tested.
  * @param {string} filename Name of the file to be deleted.
@@ skipping 151 matching lines @@
  * Obtains the preferences.
  * @param {function(Object)} callback Callback function with results returned by
  *     the script.
  */
 test.util.async.getPreferences = function(callback) {
   chrome.fileManagerPrivate.getPreferences(callback);
 };
 
 // Register the test utils.
 test.util.registerRemoteTestUtils();