[ThreadPool] Rename remaining types

 * SchedulerWorker => WorkerThread
 * SchedulerWorkerPool => ThreadGroup
 * SchedulerWorkerPoolParams => ThreadGroupParams
 * PlatformNativeWorkerPool => ThreadGroupNative
 * Scheduler*TaskRunner* => Pooled*TaskRunner*
  (including SchedulerSingleThreadTaskRunnerManager)

 => Used tools/git/move_source_file.py for move.
 => Used mass-search-and-replace with above names
 => Also mass-renamed variable in snake_case matching above names.
 => Manually searched for "WorkerPool" and fixed remaining usage.

 * SchedulerFooTest/ThreadPoolFooTest => FooTest
   (for types that are standalone; kept ThreadPool* prefix for some)

 * Also renamed remaining "Scheduler" nomenclature in
   components/thread_pool_util (means variations names are changing)

[email protected]

TBR=eroman (net/ side-effects)
TBR=ganesh (chrome/updater side-effects)

Bug: 951388
Change-Id: Iff84e4d37ed0942c4ff8c6fb4029478e8ce1529b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1590408
Commit-Queue: Gabriel Charette <[email protected]>
Reviewed-by: François Doray <[email protected]>
Reviewed-by: Lei Zhang <[email protected]>
Reviewed-by: Rohit Rao <[email protected]>
Reviewed-by: David Bienvenu <[email protected]>
Reviewed-by: Avi Drissman <[email protected]>
Cr-Commit-Position: refs/heads/master@{#655594}
diff --git a/base/task_runner.cc b/base/task_runner.cc
index aae9f9ec..73130163 100644
--- a/base/task_runner.cc
+++ b/base/task_runner.cc
@@ -15,7 +15,7 @@
 namespace {
 
 // TODO(akalin): There's only one other implementation of
-// PostTaskAndReplyImpl in WorkerPool.  Investigate whether it'll be
+// PostTaskAndReplyImpl in post_task.cc.  Investigate whether it'll be
 // possible to merge the two.
 class PostTaskAndReplyTaskRunner : public internal::PostTaskAndReplyImpl {
  public: