Standardize usage of virtual/override/final in sync/

sync/internal_api/public/engine/model_safe_worker.h

 // 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.
 
 #ifndef SYNC_INTERNAL_API_PUBLIC_ENGINE_MODEL_SAFE_WORKER_H_
 #define SYNC_INTERNAL_API_PUBLIC_ENGINE_MODEL_SAFE_WORKER_H_
 
 #include <map>
 #include <string>
 #include <vector>
@@ skipping 71 matching lines @@
   // return CANNOT_DO_WORK.
   SyncerError DoWorkAndWaitUntilDone(const WorkCallback& work);
 
   // Soft stop worker by setting stopped_ flag. Called when sync is disabled
   // or browser is shutting down. Called on UI loop.
   virtual void RequestStop();
 
   virtual ModelSafeGroup GetModelSafeGroup() = 0;
 
   // MessageLoop::DestructionObserver implementation.
-  virtual void WillDestroyCurrentMessageLoop() override;
+  void WillDestroyCurrentMessageLoop() override;
 
  protected:
   friend class base::RefCountedThreadSafe<ModelSafeWorker>;
 
   explicit ModelSafeWorker(WorkerLoopDestructionObserver* observer);
-  virtual ~ModelSafeWorker();
+  ~ModelSafeWorker() override;
 
   // Any time the Syncer performs model modifications (e.g employing a
   // WriteTransaction), it should be done by this method to ensure it is done
   // from a model-safe thread.
   virtual SyncerError DoWorkAndWaitUntilDoneImpl(const WorkCallback& work) = 0;
 
   base::WaitableEvent* work_done_or_stopped() {
     return &work_done_or_stopped_;
   }
 
@@ skipping 48 matching lines @@
 SYNC_EXPORT ModelTypeSet GetRoutingInfoTypes(
     const ModelSafeRoutingInfo& routing_info);
 
 SYNC_EXPORT ModelSafeGroup GetGroupForModelType(
     const ModelType type,
     const ModelSafeRoutingInfo& routes);
 
 }  // namespace syncer
 
 #endif  // SYNC_INTERNAL_API_PUBLIC_ENGINE_MODEL_SAFE_WORKER_H_