Fix virtual/override/final usage in Source/modules/.

Source/modules/serviceworkers/ServiceWorkerThread.h

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 23 matching lines @@
 #include "core/workers/WorkerThread.h"
 #include "modules/ModulesExport.h"
 
 namespace blink {
 
 class WorkerThreadStartupData;
 
 class MODULES_EXPORT ServiceWorkerThread final : public WorkerThread {
 public:
     static PassRefPtr<ServiceWorkerThread> create(PassRefPtr<WorkerLoaderProxy>, WorkerReportingProxy&);
-    virtual ~ServiceWorkerThread();
+    ~ServiceWorkerThread() override;
 
 protected:
     PassRefPtrWillBeRawPtr<WorkerGlobalScope> createWorkerGlobalScope(PassOwnPtr<WorkerThreadStartupData>) override;
     WebThreadSupportingGC& backingThread() override;
 
 private:
     ServiceWorkerThread(PassRefPtr<WorkerLoaderProxy>, WorkerReportingProxy&);
 
     OwnPtr<WebThreadSupportingGC> m_thread;
 };
 
 } // namespace blink
 
 #endif // ServiceWorkerThread_h