Task Scheduler API migration: change BrowserThreadModelWorker to SequencedModelWorker

components/sync/engine/browser_thread_model_worker.cc

-// Copyright 2012 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.
-
-#include "components/sync/engine/browser_thread_model_worker.h"
-
-#include <utility>
-
-namespace syncer {
-
-BrowserThreadModelWorker::BrowserThreadModelWorker(
-    const scoped_refptr<base::SingleThreadTaskRunner>& runner,
-    ModelSafeGroup group)
-    : runner_(runner), group_(group) {}
-
-void BrowserThreadModelWorker::ScheduleWork(base::OnceClosure work) {
-  if (runner_->BelongsToCurrentThread()) {
-    DLOG(WARNING) << "Already on thread " << runner_;
-    std::move(work).Run();
-  } else {
-    runner_->PostTask(FROM_HERE, std::move(work));
-  }
-}
-
-ModelSafeGroup BrowserThreadModelWorker::GetModelSafeGroup() {
-  return group_;
-}
-
-bool BrowserThreadModelWorker::IsOnModelThread() {
-  return runner_->BelongsToCurrentThread();
-}
-
-BrowserThreadModelWorker::~BrowserThreadModelWorker() {}
-
-}  // namespace syncer