Files.app: Fix the flakyness in CreateNewFolderTest and re-enable it

chrome/browser/chromeos/file_manager/file_manager_browsertest.cc

 // 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.
 
 // Browser test for basic Chrome OS file manager functionality:
 //  - The file list is updated when a file is added externally to the Downloads
 //    folder.
 //  - Selecting a file and copy-pasting it with the keyboard copies the file.
 //  - Selecting a file and pressing delete deletes it.
 
@@ skipping 797 matching lines @@
     ::testing::Values(
         TestParameter(IN_GUEST_MODE, "audioOpenDownloads"),
         TestParameter(NOT_IN_GUEST_MODE, "audioOpenDownloads"),
         TestParameter(NOT_IN_GUEST_MODE, "audioOpenDrive"),
         TestParameter(NOT_IN_GUEST_MODE, "audioAutoAdvanceDrive"),
         TestParameter(NOT_IN_GUEST_MODE, "audioRepeatSingleFileDrive"),
         TestParameter(NOT_IN_GUEST_MODE, "audioNoRepeatSingleFileDrive"),
         TestParameter(NOT_IN_GUEST_MODE, "audioRepeatMultipleFileDrive"),
         TestParameter(NOT_IN_GUEST_MODE, "audioNoRepeatMultipleFileDrive")));
 
-// Disabled due to frequent failure: http://crbug.com/377636
+// Slow tests are disabled on debug build. http://crbug.com/327719
+#if !defined(NDEBUG)
+#define MAYBE_CreateNewFolder DISABLED_CreateNewFolder
+#else
+#define MAYBE_CreateNewFolder CreateNewFolder
+#endif
 INSTANTIATE_TEST_CASE_P(
-    DISABLED_CreateNewFolder,
+    MAYBE_CreateNewFolder,
     FileManagerBrowserTest,
     ::testing::Values(TestParameter(NOT_IN_GUEST_MODE,
                                     "createNewFolderAfterSelectFile"),
                       TestParameter(IN_GUEST_MODE,
                                     "createNewFolderDownloads"),
                       TestParameter(NOT_IN_GUEST_MODE,
                                     "createNewFolderDownloads"),
                       TestParameter(NOT_IN_GUEST_MODE,
                                     "createNewFolderDrive")));
 
@@ skipping 524 matching lines @@
 }
 
 IN_PROC_BROWSER_TEST_F(GalleryBrowserTest, DeleteImageOnDrive) {
   AddScript("gallery/slide_mode.js");
   set_test_case_name("deleteImageOnDrive");
   StartTest();
 }
 
 }  // namespace
 }  // namespace file_manager