[Files.app] Add a test to check tabfocus

ui/file_manager/integration_tests/remote_call.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.
 
 'use strict';
 
 /**
  * Class to manipulate the window in the remote extension.
  *
  * @param {string} extensionId ID of extension to be manipulated.
@@ skipping 314 matching lines @@
   return repeatUntil(function() {
     return this.callRemoteTestUtil('getExecutedTasks', windowId, []).
         then(function(executedTasks) {
           if (executedTasks.indexOf(taskId) === -1)
             return pending('Executed task is %j', executedTasks);
         });
   }.bind(this));
 };
 
 /**
+ * Check if the next tabforcus'd element has the given ID or not.
+ * @param {string} windowId Target window ID.
+ * @param {string} elementId String of 'id' attribute which the next tabfocus'd
+ *     element should have.
+ * @return {Promise} Promise to be fulfilled with the result.
+ */
+RemoteCallFilesApp.prototype.checkNextTabFocus =
+    function(windowId, elementId) {
+  return remoteCall.callRemoteTestUtil('fakeKeyDown',
+                                       windowId,
+                                       ['body', 'U+0009', false]).then(
+  function(result) {
+    chrome.test.assertTrue(result);
+    return remoteCall.callRemoteTestUtil('getActiveElement',
+                                         windowId,
+                                         []);
+  }).then(function(element) {
+    if (!element || !element.attributes['id'])
+      return false;
+
+    if (element.attributes['id'] === elementId) {
+      return true;
+    } else {
+      console.error('The ID of the element should be "' + elementId +
+                    '", but "' + element.attributes['id'] + '"');
+      return false;
+    }
+  });
+};
+
+/**
  * Waits until the current directory is changed.
  * @param {string} windowId Target window ID.
  * @param {string} expectedPath Path to be changed to.
  * @return {Promise} Promise to be fulfilled when the current directory is
  *     changed to expectedPath.
  */
 RemoteCallFilesApp.prototype.waitUntilCurrentDirectoryIsChanged =
     function(windowId, expectedPath) {
   return repeatUntil(function () {
     return this.callRemoteTestUtil('getBreadcrumbPath', windowId, []).then(
@@ skipping 87 matching lines @@
  * @param {AppWindow} appWindow App window.
  * @return {Promise} Promise to be fulfilled when the element appears.
  */
 RemoteCallGallery.prototype.waitForPressEnterMessage = function(appId) {
   return this.waitForElement(appId, '.prompt-wrapper .prompt').
       then(function(element) {
         chrome.test.assertEq(
             'Press Enter when done', element.text.trim());
       });
 };