Fix typo in TaskScheduler, enable associated test

Fix comment typo in
https://chromium-review.googlesource.com/c/chromium/src/+/721570/, and
also enable IndexedDBFactoryTest.DataFormatVersion which should now not
flake on Fuchsia.

Bug: 771701
Change-Id: I7a67bf762cbf171965cb1f2810100945f685327e
Reviewed-on: https://chromium-review.googlesource.com/723562
Commit-Queue: Scott Graham <scottmg@chromium.org>
Commit-Queue: Gabriel Charette <gab@chromium.org>
Reviewed-by: Gabriel Charette <gab@chromium.org>
Cr-Commit-Position: refs/heads/master@{#509545}

base/task_scheduler/task_scheduler_impl.cc

@@ -172,7 +172,7 @@ void TaskSchedulerImpl::JoinForTesting() {
   DCHECK(!join_for_testing_returned_.IsSet());
 #endif
   // The service thread must be stopped before the workers are joined, otherwise
-  // tasks scheduled by the DeferredTaskManager might be posted between joining
+  // tasks scheduled by the DelayedTaskManager might be posted between joining
   // those workers and stopping the service thread which will cause a CHECK. See
   // https://crbug.com/771701.
   service_thread_.Stop();

testing/buildbot/filters/fuchsia.content_unittests.filter

 # Being ported, https://crbug.com/754861.
 
-
-# Crashes occasionally, possibly related to https://crbug.com/758634.
--IndexedDBFactoryTest.DataFormatVersion
-
 # These rely on chmod() for MakeFileUnread/writable(), https://crbug.com/759853.
 -BaseFileTest.ReadonlyBaseFile
 -BaseFileTest.RenameWithError