Remove outdated TODO

R=hajimehoshi@chromium.org, haraken@chromium.org

Bug: 870606
Change-Id: I99c11a168b13e8492ef05de7bca69843d9bec4f9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2396600Reviewed-by: Kentaro Hara <haraken@chromium.org>
Commit-Queue: Dominic Farolino <dom@chromium.org>
Cr-Commit-Position: refs/heads/master@{#804823}

third_party/blink/renderer/platform/scheduler/main_thread/main_thread_scheduler_helper.cc

@@ -16,8 +16,6 @@ MainThreadSchedulerHelper::MainThreadSchedulerHelper(
     MainThreadSchedulerImpl* main_thread_scheduler)
     : SchedulerHelper(sequence_manager),
       main_thread_scheduler_(main_thread_scheduler),
-      // TODO(hajimehoshi): Forbid V8 execution at |default_task_queue_|
-      // (crbug.com/870606).
       default_task_queue_(
           NewTaskQueue(MainThreadTaskQueue::QueueCreationParams(
                            MainThreadTaskQueue::QueueType::kDefault)