Cleanup: Remove unneeded browser_thread.h usage.

chrome/browser/sync/glue/history_model_worker.cc

 // Copyright (c) 2010 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 "chrome/browser/sync/glue/history_model_worker.h"
 
 #include "base/message_loop.h"
 #include "base/ref_counted.h"
 #include "base/task.h"
 #include "base/waitable_event.h"
-#include "chrome/browser/browser_thread.h"
 #include "chrome/browser/history/history.h"
 
 using base::WaitableEvent;
 
 namespace browser_sync {
 
 class WorkerTask : public HistoryDBTask {
  public:
   WorkerTask(Callback0::Type* work, WaitableEvent* done)
     : work_(work), done_(done) {}
@@ skipping 28 matching lines @@
   history_service_->ScheduleDBTask(task.get(), this);
   done.Wait();
 }
 
 bool HistoryModelWorker::CurrentThreadIsWorkThread() {
   // TODO(ncarter): How to determine this?
   return true;
 }
 
 }  // namespace browser_sync