Convert gear_menu.js to use async-await.

Bug: 909056
Change-Id: Ic571f2d16d9d906bc176d34f539e53f57b2acbb3
Reviewed-on: https://chromium-review.googlesource.com/c/1355301Reviewed-by: Luciano Pacheco <lucmult@chromium.org>
Commit-Queue: Sam McNally <sammc@chromium.org>
Cr-Commit-Position: refs/heads/master@{#612530}

ui/file_manager/integration_tests/file_manager/gear_menu.js

@@ -71,11 +71,10 @@ const BASIC_DRIVE_ENTRY_SET_WITHOUT_GDOCS = [
  * @param {!Array<!TestEntryInfo>} basicSet Files expected before showing hidden
  * @param {!Array<!TestEntryInfo>} hiddenEntrySet Files expected after showing
  * hidden
- * @return {!Array} The test steps to toggle hidden files
  */
-function getTestCaseStepsForHiddenFiles(basicSet, hiddenEntrySet) {
-  return getTestCaseStepsForHiddenFilesWithMenuItem(
-      basicSet, hiddenEntrySet, '#gear-menu-toggle-hidden-files');
+function runHiddenFilesTest(appId, basicSet, hiddenEntrySet) {
+  return runHiddenFilesTestWithMenuItem(
+      appId, basicSet, hiddenEntrySet, '#gear-menu-toggle-hidden-files');
 }
 
 /**
@@ -83,11 +82,11 @@ function getTestCaseStepsForHiddenFiles(basicSet, hiddenEntrySet) {
  * @param {!Array<!TestEntryInfo>} basicSet Files expected before showing hidden
  * @param {!Array<!TestEntryInfo>} hiddenEntrySet Files expected after showing
  * hidden
- * @return {!Array} The test steps to toggle hidden files
  */
-function getTestCaseStepsForAndroidHiddenFiles(basicSet, hiddenEntrySet) {
-  return getTestCaseStepsForHiddenFilesWithMenuItem(
-      basicSet, hiddenEntrySet, '#gear-menu-toggle-hidden-android-folders');
+function runAndroidHiddenFilesTest(appId, basicSet, hiddenEntrySet) {
+  return runHiddenFilesTestWithMenuItem(
+      appId, basicSet, hiddenEntrySet,
+      '#gear-menu-toggle-hidden-android-folders');
 }
 
 /**
@@ -97,669 +96,377 @@ function getTestCaseStepsForAndroidHiddenFiles(basicSet, hiddenEntrySet) {
  * hidden
  * @param {string} toggleMenuItemSelector Selector for the menu item that
  * toggles hidden file visibility
- * @return {!Array} The test steps to toggle hidden files
  */
-function getTestCaseStepsForHiddenFilesWithMenuItem(
-    basicSet, hiddenEntrySet, toggleMenuItemSelector) {
-  var appId;
-  return [
-    function(id) {
-      appId = id;
-      remoteCall.waitForElement(appId, '#gear-button:not([hidden])')
-          .then(this.next);
-    },
+async function runHiddenFilesTestWithMenuItem(
+    appId, basicSet, hiddenEntrySet, toggleMenuItemSelector) {
+  await remoteCall.waitForElement(appId, '#gear-button:not([hidden])');
+
   // Open the gear menu by clicking the gear button.
-    function() {
-      remoteCall.callRemoteTestUtil(
-          'fakeMouseClick', appId, ['#gear-button'], this.next);
-    },
+  chrome.test.assertTrue(await remoteCall.callRemoteTestUtil(
+      'fakeMouseClick', appId, ['#gear-button']));
+
   // Wait for menu to not be hidden.
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall.waitForElement(appId, '#gear-menu:not([hidden])')
-      .then(this.next);
-    },
+  await remoteCall.waitForElement(appId, '#gear-menu:not([hidden])');
+
   // Wait for menu item to appear.
-    function(result) {
-      remoteCall
-          .waitForElement(appId, toggleMenuItemSelector + ':not([disabled])')
-          .then(this.next);
-    },
+  await remoteCall.waitForElement(
+      appId, toggleMenuItemSelector + ':not([disabled])');
+
   // Wait for menu item to appear.
-    function(result) {
-      remoteCall
-          .waitForElement(appId, toggleMenuItemSelector + ':not([checked])')
-          .then(this.next);
-    },
+  await remoteCall.waitForElement(
+      appId, toggleMenuItemSelector + ':not([checked])');
+
   // Click the menu item.
-    function(results) {
-      remoteCall.callRemoteTestUtil(
-          'fakeMouseClick', appId, [toggleMenuItemSelector], this.next);
-    },
+  chrome.test.assertTrue(await remoteCall.callRemoteTestUtil(
+      'fakeMouseClick', appId, [toggleMenuItemSelector]));
+
   // Wait for item to be checked.
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall.waitForElement(appId, toggleMenuItemSelector + '[checked]')
-          .then(this.next);
-    },
+  await remoteCall.waitForElement(appId, toggleMenuItemSelector + '[checked]');
+
   // Check the hidden files are displayed.
-    function(result) {
-      remoteCall.waitForFiles(appId, TestEntryInfo.getExpectedRows(
-          hiddenEntrySet), {ignoreFileSize: true, ignoreLastModifiedTime: true})
-          .then(this.next);
-    },
+  await remoteCall.waitForFiles(
+      appId, TestEntryInfo.getExpectedRows(hiddenEntrySet),
+      {ignoreFileSize: true, ignoreLastModifiedTime: true});
+
   // Repeat steps to toggle again.
-    function(inAppId) {
-      remoteCall.waitForElement(appId, '#gear-button:not([hidden])')
-          .then(this.next);
-    },
-    function() {
-      remoteCall.callRemoteTestUtil(
-          'fakeMouseClick', appId, ['#gear-button'], this.next);
-    },
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall.waitForElement(appId, '#gear-menu:not([hidden])').then(
-          this.next);
-    },
-    function(result) {
-      remoteCall
-          .waitForElement(appId, toggleMenuItemSelector + ':not([disabled])')
-          .then(this.next);
-    },
-    function(result) {
-      remoteCall.waitForElement(appId, toggleMenuItemSelector + '[checked]')
-          .then(this.next);
-    },
-    function(results) {
-      remoteCall.callRemoteTestUtil(
-          'fakeMouseClick', appId, [toggleMenuItemSelector], this.next);
-    },
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall
-          .waitForElement(appId, toggleMenuItemSelector + ':not([checked])')
-          .then(this.next);
-    },
-    function(result) {
-      remoteCall.waitForFiles(appId, TestEntryInfo.getExpectedRows(basicSet),
-          {ignoreFileSize: true, ignoreLastModifiedTime: true}).then(this.next);
-    },
-    function() {
-      checkIfNoErrorsOccured(this.next);
-    },
-  ];
+  await remoteCall.waitForElement(appId, '#gear-button:not([hidden])');
+  chrome.test.assertTrue(await remoteCall.callRemoteTestUtil(
+      'fakeMouseClick', appId, ['#gear-button']));
+
+  await remoteCall.waitForElement(appId, '#gear-menu:not([hidden])');
+  await remoteCall.waitForElement(
+      appId, toggleMenuItemSelector + ':not([disabled])');
+  await remoteCall.waitForElement(appId, toggleMenuItemSelector + '[checked]');
+  chrome.test.assertTrue(await remoteCall.callRemoteTestUtil(
+      'fakeMouseClick', appId, [toggleMenuItemSelector]));
+
+  await remoteCall.waitForElement(
+      appId, toggleMenuItemSelector + ':not([checked])');
+  await remoteCall.waitForFiles(
+      appId, TestEntryInfo.getExpectedRows(basicSet),
+      {ignoreFileSize: true, ignoreLastModifiedTime: true});
 }
 
 /**
  * Tests toggling the show-hidden-files menu option on Downloads.
  */
-testcase.showHiddenFilesDownloads = function() {
-  var appId;
-  var steps = [
-    function() {
-      addEntries(['local'], BASIC_LOCAL_ENTRY_SET_WITH_HIDDEN, this.next);
-    },
-    function(result) {
-      chrome.test.assertTrue(result);
-      openNewWindow(null, RootPath.DOWNLOADS).then(this.next);
-    },
-    function(inAppId) {
-      appId = inAppId;
-      remoteCall.waitForElement(appId, '#detail-table').then(this.next);
-    },
-    // Wait for volume list to be initialized.
-    function() {
-      remoteCall.waitForFileListChange(appId, 0).then(this.next);
-    },
-    function() {
-      this.next(appId);
-    },
-  ];
-
-  steps = steps.concat(getTestCaseStepsForHiddenFiles(BASIC_LOCAL_ENTRY_SET,
-    BASIC_LOCAL_ENTRY_SET_WITH_HIDDEN));
-  StepsRunner.run(steps);
-};
+testcase.showHiddenFilesDownloads = async function() {
+  const {appId} = await setupAndWaitUntilReady(
+      null, RootPath.DOWNLOADS, null, BASIC_LOCAL_ENTRY_SET_WITH_HIDDEN, []);
 
+  await runHiddenFilesTest(
+      appId, BASIC_LOCAL_ENTRY_SET, BASIC_LOCAL_ENTRY_SET_WITH_HIDDEN);
+};
 
 /**
  * Tests toggling the show-hidden-files menu option on Drive.
  */
-testcase.showHiddenFilesDrive = function() {
-  var appId;
-  var steps = [
-    function() {
-      addEntries(['drive'], BASIC_DRIVE_ENTRY_SET_WITH_HIDDEN, this.next);
-    },
-    function(result) {
-      chrome.test.assertTrue(result);
-      openNewWindow(null, RootPath.DRIVE).then(this.next);
-    },
-    function(inAppId) {
-      appId = inAppId;
-      remoteCall.waitForElement(appId, '#detail-table').then(this.next);
-    },
-    // Wait for volume list to be initialized.
-    function() {
-      remoteCall.waitForFileListChange(appId, 0).then(this.next);
-    },
-    function() {
-      this.next(appId);
-    },
-  ];
-
-  steps = steps.concat(getTestCaseStepsForHiddenFiles(BASIC_DRIVE_ENTRY_SET,
-    BASIC_DRIVE_ENTRY_SET_WITH_HIDDEN));
-  StepsRunner.run(steps);
+testcase.showHiddenFilesDrive = async function() {
+  const {appId} = await setupAndWaitUntilReady(
+      null, RootPath.DRIVE, null, [], BASIC_DRIVE_ENTRY_SET_WITH_HIDDEN);
+
+  await runHiddenFilesTest(
+      appId, BASIC_DRIVE_ENTRY_SET, BASIC_DRIVE_ENTRY_SET_WITH_HIDDEN);
 };
 
 /**
  * Tests that toggle-hidden-android-folders menu item exists when "Play files"
  * is selected, but hidden in Recents.
  */
-testcase.showToggleHiddenAndroidFoldersGearMenuItemsInMyFiles = function() {
-  var appId;
-  StepsRunner.run([
+testcase.showToggleHiddenAndroidFoldersGearMenuItemsInMyFiles =
+    async function() {
   // Open Files.App on Play Files.
-    function() {
-      openNewWindow(null, RootPath.ANDROID_FILES).then(this.next);
-    },
-    function(inAppId) {
-      appId = inAppId;
-      addEntries(['android_files'], BASIC_ANDROID_ENTRY_SET, this.next);
-    },
+  const appId = await openNewWindow(null, RootPath.ANDROID_FILES);
+  await addEntries(['android_files'], BASIC_ANDROID_ENTRY_SET);
+
   // Wait for the file list to appear.
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall.waitForElement(appId, '#file-list').then(this.next);
-    },
+  await remoteCall.waitForElement(appId, '#file-list');
+
   // Wait for the gear menu button to appear.
-    function() {
-      remoteCall.waitForElement(appId, '#gear-button:not([hidden])')
-          .then(this.next);
-    },
+  await remoteCall.waitForElement(appId, '#gear-button:not([hidden])');
+
   // Click the gear menu button.
-    function() {
-      remoteCall.callRemoteTestUtil(
-          'fakeMouseClick', appId, ['#gear-button'], this.next);
-    },
+  chrome.test.assertTrue(await remoteCall.callRemoteTestUtil(
+      'fakeMouseClick', appId, ['#gear-button']));
+
   // Wait for the gear menu to appear.
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall.waitForElement(appId, '#gear-menu:not([hidden])')
-          .then(this.next);
-    },
+  await remoteCall.waitForElement(appId, '#gear-menu:not([hidden])');
+
   // #toggle-hidden-android-folders command should be shown and disabled by
   // default.
-    function() {
-      remoteCall
-          .waitForElement(
+  await remoteCall.waitForElement(
       appId,
       '#gear-menu-toggle-hidden-android-folders' +
-                  ':not([checked]):not([hidden])')
-          .then(this.next);
-    },
+          ':not([checked]):not([hidden])');
+
   // Click the file list: the gear menu should hide.
-    function() {
-      remoteCall.callRemoteTestUtil(
-          'fakeMouseClick', appId, ['#file-list'], this.next);
-    },
+  chrome.test.assertTrue(await remoteCall.callRemoteTestUtil(
+      'fakeMouseClick', appId, ['#file-list']));
+
   // Wait for the gear menu to hide.
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall.waitForElement(appId, '#gear-menu[hidden]').then(this.next);
-    },
+  await remoteCall.waitForElement(appId, '#gear-menu[hidden]');
+
   // Navigate to Recent.
-    function() {
-      remoteCall.callRemoteTestUtil(
-          'fakeMouseClick', appId, ['span[root-type-icon=\'recent\']'],
-          this.next);
-    },
+  chrome.test.assertTrue(await remoteCall.callRemoteTestUtil(
+      'fakeMouseClick', appId, ['span[root-type-icon=\'recent\']']));
+
   // Click the gear menu button.
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall.callRemoteTestUtil(
-          'fakeMouseClick', appId, ['#gear-button'], this.next);
-    },
+  chrome.test.assertTrue(await remoteCall.callRemoteTestUtil(
+      'fakeMouseClick', appId, ['#gear-button']));
+
   // Wait for the gear menu to appear.
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall.waitForElement(appId, '#gear-menu:not([hidden])')
-          .then(this.next);
-    },
+  await remoteCall.waitForElement(appId, '#gear-menu:not([hidden])');
+
   // #toggle-hidden-android-folders command should be hidden.
-    function(result) {
-      remoteCall
-          .waitForElement(
-              appId, '#gear-menu-toggle-hidden-android-folders[hidden]')
-          .then(this.next);
-    },
-    function() {
-      checkIfNoErrorsOccured(this.next);
-    },
-  ]);
+  await remoteCall.waitForElement(
+      appId, '#gear-menu-toggle-hidden-android-folders[hidden]');
 };
 
 /**
  * Tests that "Play files" shows the full set of files after
  * toggle-hidden-android-folders is enabled.
  */
-testcase.enableToggleHiddenAndroidFoldersShowsHiddenFiles = function() {
-  var appId;
-  var steps = [
+testcase.enableToggleHiddenAndroidFoldersShowsHiddenFiles = async function() {
   // Open Files.App on Play Files.
-    function() {
-      openNewWindow(null, RootPath.ANDROID_FILES).then(this.next);
-    },
-    function(inAppId) {
-      appId = inAppId;
-      addEntries(
-          ['android_files'], BASIC_ANDROID_ENTRY_SET_WITH_HIDDEN, this.next);
-    },
+  const appId = await openNewWindow(null, RootPath.ANDROID_FILES);
+  await addEntries(['android_files'], BASIC_ANDROID_ENTRY_SET_WITH_HIDDEN);
+
   // Wait for the file list to appear.
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall.waitForElement(appId, '#file-list').then(this.next);
-    },
+  await remoteCall.waitForElement(appId, '#file-list');
+
   // Wait for the gear menu button to appear.
-    function() {
-      remoteCall.waitForElement(appId, '#gear-button:not([hidden])')
-          .then(this.next);
-    },
-    function() {
-      this.next(appId);
-    }
-  ];
-  steps = steps.concat(getTestCaseStepsForAndroidHiddenFiles(
-      BASIC_ANDROID_ENTRY_SET, BASIC_ANDROID_ENTRY_SET_WITH_HIDDEN));
-  StepsRunner.run(steps);
+  await remoteCall.waitForElement(appId, '#gear-button:not([hidden])');
+  await runAndroidHiddenFilesTest(
+      appId, BASIC_ANDROID_ENTRY_SET, BASIC_ANDROID_ENTRY_SET_WITH_HIDDEN);
 };
 
 /**
  * Tests that the current directory is changed to "Play files" after the
  * current directory is hidden by toggle-hidden-android-folders option.
  */
-testcase.hideCurrentDirectoryByTogglingHiddenAndroidFolders = function() {
-  let appId;
+testcase.hideCurrentDirectoryByTogglingHiddenAndroidFolders = async function() {
   const MENU_ITEM_SELECTOR = '#gear-menu-toggle-hidden-android-folders';
-  const steps = [
-    function() {
-      openNewWindow(null, RootPath.ANDROID_FILES).then(this.next);
-    },
-    function(inAppId) {
-      appId = inAppId;
-      addEntries(
-          ['android_files'], BASIC_ANDROID_ENTRY_SET_WITH_HIDDEN, this.next);
-    },
+  const appId = await openNewWindow(null, RootPath.ANDROID_FILES);
+  await addEntries(['android_files'], BASIC_ANDROID_ENTRY_SET_WITH_HIDDEN);
+
   // Wait for the file list to appear.
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall.waitForElement(appId, '#file-list').then(this.next);
-    },
+  await remoteCall.waitForElement(appId, '#file-list');
+
   // Wait for the gear menu button to appear.
-    function() {
-      remoteCall.waitForElement(appId, '#gear-button:not([hidden])')
-          .then(this.next);
-    },
+  await remoteCall.waitForElement(appId, '#gear-button:not([hidden])');
+
   // Open the gear menu by clicking the gear button.
-    function() {
-      remoteCall.callRemoteTestUtil(
-          'fakeMouseClick', appId, ['#gear-button'], this.next);
-    },
+  chrome.test.assertTrue(await remoteCall.callRemoteTestUtil(
+      'fakeMouseClick', appId, ['#gear-button']));
+
   // Wait for menu to not be hidden.
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall.waitForElement(appId, '#gear-menu:not([hidden])')
-          .then(this.next);
-    },
+  await remoteCall.waitForElement(appId, '#gear-menu:not([hidden])');
+
   // Wait for menu item to appear.
-    function() {
-      remoteCall
-          .waitForElement(
-              appId, MENU_ITEM_SELECTOR + ':not([disabled]):not([checked])')
-          .then(this.next);
-    },
+  await remoteCall.waitForElement(
+      appId, MENU_ITEM_SELECTOR + ':not([disabled]):not([checked])');
+
   // Click the menu item.
-    function() {
-      remoteCall.callRemoteTestUtil(
-          'fakeMouseClick', appId, [MENU_ITEM_SELECTOR], this.next);
-    },
+  chrome.test.assertTrue(await remoteCall.callRemoteTestUtil(
+      'fakeMouseClick', appId, [MENU_ITEM_SELECTOR]));
+
   // Wait for item to be checked.
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall.waitForElement(appId, MENU_ITEM_SELECTOR + '[checked]')
-          .then(this.next);
-    },
+  await remoteCall.waitForElement(appId, MENU_ITEM_SELECTOR + '[checked]');
+
   // Check the hidden files are displayed.
-    function() {
-      remoteCall
-          .waitForFiles(
-              appId,
-              TestEntryInfo.getExpectedRows(
-                  BASIC_ANDROID_ENTRY_SET_WITH_HIDDEN),
-              {ignoreFileSize: true, ignoreLastModifiedTime: true})
-          .then(this.next);
-    },
+  await remoteCall.waitForFiles(
+      appId, TestEntryInfo.getExpectedRows(BASIC_ANDROID_ENTRY_SET_WITH_HIDDEN),
+      {ignoreFileSize: true, ignoreLastModifiedTime: true});
+
   // Navigate to "/My files/Play files/A".
-    function() {
-      remoteCall
-          .navigateWithDirectoryTree(
-              appId, '/A', 'My files/Play files', 'android_files')
-          .then(this.next);
-    },
+  await remoteCall.navigateWithDirectoryTree(
+      appId, '/A', 'My files/Play files', 'android_files');
+
   // Wait until current directory is changed to "/My files/Play files/A".
-    function() {
-      remoteCall
-          .waitUntilCurrentDirectoryIsChanged(appId, '/My files/Play files/A')
-          .then(this.next);
-    },
+  await remoteCall.waitUntilCurrentDirectoryIsChanged(
+      appId, '/My files/Play files/A');
+
   // Open the gear menu by clicking the gear button.
-    function() {
-      remoteCall.callRemoteTestUtil(
-          'fakeMouseClick', appId, ['#gear-button'], this.next);
-    },
+  chrome.test.assertTrue(await remoteCall.callRemoteTestUtil(
+      'fakeMouseClick', appId, ['#gear-button']));
+
   // Wait for menu to not be hidden.
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall.waitForElement(appId, '#gear-menu:not([hidden])')
-          .then(this.next);
-    },
+  await remoteCall.waitForElement(appId, '#gear-menu:not([hidden])');
+
   // Wait for menu item to appear.
-    function() {
-      remoteCall
-          .waitForElement(
-              appId, MENU_ITEM_SELECTOR + '[checked]:not([disabled])')
-          .then(this.next);
-    },
+  await remoteCall.waitForElement(
+      appId, MENU_ITEM_SELECTOR + '[checked]:not([disabled])');
+
   // Click the menu item.
-    function() {
-      remoteCall.callRemoteTestUtil(
-          'fakeMouseClick', appId, [MENU_ITEM_SELECTOR], this.next);
-    },
+  chrome.test.assertTrue(await remoteCall.callRemoteTestUtil(
+      'fakeMouseClick', appId, [MENU_ITEM_SELECTOR]));
+
   // Wait until the current directory is changed from
   // "/My files/Play files/A" to "/My files/Play files" since
   // "/My files/Play files/A" is invisible now.
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall
-          .waitUntilCurrentDirectoryIsChanged(appId, '/My files/Play files')
-          .then(this.next);
-    },
-    function() {
-      checkIfNoErrorsOccured(this.next);
-    },
-  ];
-  StepsRunner.run(steps);
+  await remoteCall.waitUntilCurrentDirectoryIsChanged(
+      appId, '/My files/Play files');
 };
 
 /**
  * Tests the paste-into-current-folder menu item.
  */
-testcase.showPasteIntoCurrentFolder = function() {
+testcase.showPasteIntoCurrentFolder = async function() {
   const entrySet = [ENTRIES.hello, ENTRIES.world];
-  var appId;
-  StepsRunner.run([
+
   // Add files to Downloads volume.
-    function() {
-      addEntries(['local'], entrySet, this.next);
-    },
+  await addEntries(['local'], entrySet);
+
   // Open Files.App on Downloads.
-    function(result) {
-      chrome.test.assertTrue(result);
-      openNewWindow(null, RootPath.DOWNLOADS).then(this.next);
-    },
-    function(inAppId) {
-      appId = inAppId;
-      remoteCall.waitForElement(appId, '#file-list').then(this.next);
-    },
+  const appId = await openNewWindow(null, RootPath.DOWNLOADS);
+  await remoteCall.waitForElement(appId, '#file-list');
+
   // Wait for the files to appear in the file list.
-    function() {
-      remoteCall.waitForFiles(appId, TestEntryInfo.getExpectedRows(entrySet))
-          .then(this.next);
-    },
+  await remoteCall.waitForFiles(appId, TestEntryInfo.getExpectedRows(entrySet));
+
   // Wait for the gear menu button to appear.
-    function() {
-      remoteCall.waitForElement(appId, '#gear-button').then(this.next);
-    },
+  await remoteCall.waitForElement(appId, '#gear-button');
 
   // 1. Before selecting entries: click the gear menu button.
-    function() {
-      remoteCall.callRemoteTestUtil(
-          'fakeMouseClick', appId, ['#gear-button'], this.next);
-    },
+  chrome.test.assertTrue(await remoteCall.callRemoteTestUtil(
+      'fakeMouseClick', appId, ['#gear-button']));
+
   // Wait for the gear menu to appear.
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall.waitForElement(appId, '#gear-menu:not([hidden])')
-          .then(this.next);
-    },
+  await remoteCall.waitForElement(appId, '#gear-menu:not([hidden])');
+
   // #paste-into-current-folder command is shown. It should be disabled
   // because no file has been copied to clipboard.
-    function(result) {
-      remoteCall
-          .waitForElement(
+  await remoteCall.waitForElement(
       appId,
       '#gear-menu cr-menu-item' +
           '[command=\'#paste-into-current-folder\']' +
-                  '[disabled]:not([hidden])')
-          .then(this.next);
-    },
-    function() {
-      remoteCall.callRemoteTestUtil(
-          'fakeMouseClick', appId, ['#file-list'], this.next);
-    },
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall.waitForElement(appId, '#gear-menu[hidden]').then(this.next);
-    },
+          '[disabled]:not([hidden])');
+  chrome.test.assertTrue(await remoteCall.callRemoteTestUtil(
+      'fakeMouseClick', appId, ['#file-list']));
+
+  await remoteCall.waitForElement(appId, '#gear-menu[hidden]');
 
   // 2. Selecting a single regular file
-    function(result) {
-      remoteCall.callRemoteTestUtil(
-          'selectFile', appId, [ENTRIES.hello.nameText], this.next);
-    },
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall.callRemoteTestUtil(
-          'fakeMouseClick', appId, ['#gear-button'], this.next);
-    },
+  chrome.test.assertTrue(await remoteCall.callRemoteTestUtil(
+      'selectFile', appId, [ENTRIES.hello.nameText]));
+
+  chrome.test.assertTrue(await remoteCall.callRemoteTestUtil(
+      'fakeMouseClick', appId, ['#gear-button']));
+
   // Wait for menu to appear.
   // The command is still shown.
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall
-          .waitForElement(
+  await remoteCall.waitForElement(
       appId,
       '#gear-menu:not([hidden]) cr-menu-item' +
           '[command=\'#paste-into-current-folder\']' +
-                  '[disabled]:not([hidden])')
-          .then(this.next);
-    },
-    function() {
-      remoteCall.callRemoteTestUtil(
-          'fakeMouseClick', appId, ['#file-list'], this.next);
-    },
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall.waitForElement(appId, '#gear-menu[hidden]').then(this.next);
-    },
+          '[disabled]:not([hidden])');
+  chrome.test.assertTrue(await remoteCall.callRemoteTestUtil(
+      'fakeMouseClick', appId, ['#file-list']));
+
+  await remoteCall.waitForElement(appId, '#gear-menu[hidden]');
 
   // 3. When ready to paste a file
-    function(result) {
-      remoteCall.callRemoteTestUtil(
-          'selectFile', appId, [ENTRIES.hello.nameText], this.next);
-    },
+  chrome.test.assertTrue(await remoteCall.callRemoteTestUtil(
+      'selectFile', appId, [ENTRIES.hello.nameText]));
+
   // Ctrl-C to copy the selected file
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall
-          .fakeKeyDown(appId, '#file-list', 'c', true, false, false)
-          .then(this.next);
-    },
-    function() {
-      remoteCall.callRemoteTestUtil(
-          'fakeMouseClick', appId, ['#gear-button'], this.next);
-    },
+  await remoteCall.fakeKeyDown(appId, '#file-list', 'c', true, false, false);
+  chrome.test.assertTrue(await remoteCall.callRemoteTestUtil(
+      'fakeMouseClick', appId, ['#gear-button']));
+
   // The command appears enabled.
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall
-          .waitForElement(
+  await remoteCall.waitForElement(
       appId,
       '#gear-menu:not([hidden])' +
           ' cr-menu-item[command=\'#paste-into-current-folder\']' +
-                  ':not([disabled]):not([hidden])')
-          .then(this.next);
-    },
-    function() {
-      remoteCall.callRemoteTestUtil(
-          'fakeMouseClick', appId, ['#file-list'], this.next);
-    },
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall.waitForElement(appId, '#gear-menu[hidden]').then(this.next);
-    },
-    function() {
-      checkIfNoErrorsOccured(this.next);
-    },
-  ]);
+          ':not([disabled]):not([hidden])');
+  chrome.test.assertTrue(await remoteCall.callRemoteTestUtil(
+      'fakeMouseClick', appId, ['#file-list']));
+
+  await remoteCall.waitForElement(appId, '#gear-menu[hidden]');
 };
 
 /**
  * Tests the "select-all" menu item.
  */
-testcase.showSelectAllInCurrentFolder = function() {
+testcase.showSelectAllInCurrentFolder = async function() {
   const entrySet = [ENTRIES.newlyAdded];
-  var appId;
-  StepsRunner.run([
+
   // Open Files.App on Downloads.
-    function() {
-      openNewWindow(null, RootPath.DOWNLOADS).then(this.next);
-    },
-    function(inAppId) {
-      appId = inAppId;
-      remoteCall.waitForElement(appId, '#file-list').then(this.next);
-    },
+  const appId = await openNewWindow(null, RootPath.DOWNLOADS);
+  await remoteCall.waitForElement(appId, '#file-list');
+
   // Wait for the gear menu button to appear.
-    function() {
-      remoteCall.waitForElement(appId, '#gear-button').then(this.next);
-    },
+  await remoteCall.waitForElement(appId, '#gear-button');
+
   // Click the gear menu button.
-    function() {
-      remoteCall.callRemoteTestUtil(
-          'fakeMouseClick', appId, ['#gear-button'], this.next);
-    },
+  chrome.test.assertTrue(await remoteCall.callRemoteTestUtil(
+      'fakeMouseClick', appId, ['#gear-button']));
+
   // Wait for the gear menu to appear.
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall.waitForElement(appId, '#gear-menu:not([hidden])')
-          .then(this.next);
-    },
+  await remoteCall.waitForElement(appId, '#gear-menu:not([hidden])');
+
   // Check: #select-all command is shown, but disabled (no files yet).
-    function(result) {
-      remoteCall
-          .waitForElement(
+  await remoteCall.waitForElement(
       appId,
       '#gear-menu cr-menu-item' +
           '[command=\'#select-all\']' +
-                  '[disabled]:not([hidden])')
-          .then(this.next);
-    },
+          '[disabled]:not([hidden])');
+
   // Click the file list: the gear menu should hide.
-    function() {
-      remoteCall.callRemoteTestUtil(
-          'fakeMouseClick', appId, ['#file-list'], this.next);
-    },
+  chrome.test.assertTrue(await remoteCall.callRemoteTestUtil(
+      'fakeMouseClick', appId, ['#file-list']));
+
   // Wait for the gear menu to hide.
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall.waitForElement(appId, '#gear-menu[hidden]').then(this.next);
-    },
+  await remoteCall.waitForElement(appId, '#gear-menu[hidden]');
+
   // Add a new file to Downloads.
-    function() {
-      addEntries(['local'], entrySet, this.next);
-    },
+  await addEntries(['local'], entrySet);
+
   // Wait for the file list change.
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall.waitForFiles(appId, TestEntryInfo.getExpectedRows(entrySet))
-          .then(this.next);
-    },
+  await remoteCall.waitForFiles(appId, TestEntryInfo.getExpectedRows(entrySet));
+
   // Click on the gear button again.
-    function(result) {
-      remoteCall.callRemoteTestUtil(
-          'fakeMouseClick', appId, ['#gear-button'], this.next);
-    },
+  chrome.test.assertTrue(await remoteCall.callRemoteTestUtil(
+      'fakeMouseClick', appId, ['#gear-button']));
+
   // Check: #select-all command is shown, and enabled (there are files).
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall
-          .waitForElement(
+  await remoteCall.waitForElement(
       appId,
       '#gear-menu:not([hidden]) cr-menu-item' +
           '[command=\'#select-all\']' +
-                  ':not([disabled]):not([hidden])')
-          .then(this.next);
-    },
+          ':not([disabled]):not([hidden])');
+
   // Click on the #gear-menu-select-all item.
-    function(results) {
-      remoteCall.callRemoteTestUtil(
-          'fakeMouseClick', appId, ['#gear-menu-select-all'], this.next);
-    },
+  chrome.test.assertTrue(await remoteCall.callRemoteTestUtil(
+      'fakeMouseClick', appId, ['#gear-menu-select-all']));
+
   // Check: the file-list should be selected.
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall.waitForElement(appId, '#file-list li[selected]')
-          .then(this.next);
-    },
-    function() {
-      checkIfNoErrorsOccured(this.next);
-    },
-  ]);
+  await remoteCall.waitForElement(appId, '#file-list li[selected]');
 };
 
 /**
  * Tests that new folder appears in the gear menu with Downloads focused in the
  * directory tree.
  */
-testcase.newFolderInDownloads = function() {
-  var appId;
-  StepsRunner.run([
-    function() {
-      setupAndWaitUntilReady(null, RootPath.DOWNLOADS, null, [ENTRIES.hello], [
-      ]).then(this.next);
-    },
+testcase.newFolderInDownloads = async function() {
+  const {appId} = await setupAndWaitUntilReady(
+      null, RootPath.DOWNLOADS, null, [ENTRIES.hello], []);
+
   // Focus the directory tree.
-    function(results) {
-      appId = results.windowId;
+  await remoteCall.callRemoteTestUtil('focus', appId, ['#directory-tree']);
 
-      remoteCall.callRemoteTestUtil('focus', appId, ['#directory-tree'])
-          .then(this.next);
-    },
   // Open the gear menu.
-    function() {
-      remoteCall.waitForElement(appId, '#gear-button').then(this.next);
-    },
+  await remoteCall.waitForElement(appId, '#gear-button');
+
   // Open the gear meny by a shortcut (Alt-E).
-    function() {
-      remoteCall.fakeKeyDown(appId, 'body', 'e', false, false, true)
-          .then(this.next);
-    },
+  chrome.test.assertTrue(
+      await remoteCall.fakeKeyDown(appId, 'body', 'e', false, false, true));
+
   // Wait for menu to appear.
-    function(result) {
-      chrome.test.assertTrue(result);
-      remoteCall.waitForElement(appId, '#gear-menu').then(this.next);
-    },
+  await remoteCall.waitForElement(appId, '#gear-menu');
+
   // Wait for menu to appear, containing new folder.
-    function(result) {
-      remoteCall
-          .waitForElement(
-              appId, '#gear-menu-newfolder:not([disabled]):not([hidden])')
-          .then(this.next);
-    },
-    function() {
-      checkIfNoErrorsOccured(this.next);
-    }
-  ]);
+  await remoteCall.waitForElement(
+      appId, '#gear-menu-newfolder:not([disabled]):not([hidden])');
 };