Fix virtual/override/final usage in the rest of Source/core/.

Source/core/events/CompositionEvent.h

 /*
  * Copyright (C) 2009 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 32 matching lines @@
     static PassRefPtrWillBeRawPtr<CompositionEvent> create(const AtomicString& type, PassRefPtrWillBeRawPtr<AbstractView> view, const String& data)
     {
         return adoptRefWillBeNoop(new CompositionEvent(type, view, data));
     }
 
     static PassRefPtrWillBeRawPtr<CompositionEvent> create(const AtomicString& type, const CompositionEventInit& initializer)
     {
         return adoptRefWillBeNoop(new CompositionEvent(type, initializer));
     }
 
-    virtual ~CompositionEvent();
+    ~CompositionEvent() override;
 
     void initCompositionEvent(const AtomicString& type, bool canBubble, bool cancelable, PassRefPtrWillBeRawPtr<AbstractView>, const String& data);
 
     String data() const { return m_data; }
 
-    virtual const AtomicString& interfaceName() const override;
+    const AtomicString& interfaceName() const override;
 
     DECLARE_VIRTUAL_TRACE();
 
 private:
     CompositionEvent();
     CompositionEvent(const AtomicString& type, PassRefPtrWillBeRawPtr<AbstractView>, const String&);
     CompositionEvent(const AtomicString& type, const CompositionEventInit&);
 
     String m_data;
 };
 
 } // namespace blink
 
 #endif // CompositionEvent_h