Disable flaky BrowsingDataLocalStorageHelperTest.DeleteSingleFile

This test have been failing on debug build.
It has been already disabled for half a year on release build.

Example failure:https://ci.chromium.org/p/chromium/builders/ci/linux-chromeos-dbg/17887

TBR: msramek@chromium.org
Bug: 1028676
Change-Id: I349a36319f321ab1654fe8b78f11e5461e7b9d26
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2132210Reviewed-by: Anatoliy Potapchuk <apotapchuk@chromium.org>
Commit-Queue: Anatoliy Potapchuk <apotapchuk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#755339}

chrome/browser/browsing_data/browsing_data_local_storage_helper_browsertest.cc

@@ -122,13 +122,8 @@ IN_PROC_BROWSER_TEST_F(BrowsingDataLocalStorageHelperTest, CallbackCompletes) {
 }
 
 // Disable due to flaky. https://crbug.com/1028676
-#if defined(NDEBUG)
-#define MAYBE_DeleteSingleFile DISABLED_DeleteSingleFile
-#else
-#define MAYBE_DeleteSingleFile DeleteSingleFile
-#endif
 IN_PROC_BROWSER_TEST_F(BrowsingDataLocalStorageHelperTest,
-                       MAYBE_DeleteSingleFile) {
+                       DISABLED_DeleteSingleFile) {
   scoped_refptr<browsing_data::LocalStorageHelper> local_storage_helper(
       new browsing_data::LocalStorageHelper(browser()->profile()));
   CreateLocalStorageFilesForTest();