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

Source/core/events/AnimationEvent.h

Index: Source/core/events/AnimationEvent.h
diff --git a/Source/core/events/AnimationEvent.h b/Source/core/events/AnimationEvent.h
index 06258708aa3d0566b5c713192e781eddf23fa83f..f7a623012f11147f5b81c8c942380899d71790ba 100644
--- a/Source/core/events/AnimationEvent.h
+++ b/Source/core/events/AnimationEvent.h
@@ -47,12 +47,12 @@ public:
         return adoptRefWillBeNoop(new AnimationEvent(type, initializer));
     }
 
-    virtual ~AnimationEvent();
+    ~AnimationEvent() override;
 
     const String& animationName() const;
     double elapsedTime() const;
 
-    virtual const AtomicString& interfaceName() const override;
+    const AtomicString& interfaceName() const override;
 
     DECLARE_VIRTUAL_TRACE();