Fix virtual/override/final usage in Source/core/{animation,css,style}/.

Source/core/animation/CompositorAnimationsTestHelper.h

 /*
  * Copyright (C) 2012 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:
  * 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 146 matching lines @@
         }
 
         WebThread* currentThread() override
         {
             return m_platform->currentThread();
         }
 
     private:
         blink::Platform* m_platform; // Not owned.
         WebCompositorSupportMock** m_compositor;
-        virtual WebCompositorSupport* compositorSupport() override { return *m_compositor; }
+        WebCompositorSupport* compositorSupport() override { return *m_compositor; }
     };
 
     WebCompositorSupportMock* m_mockCompositor;
     PlatformProxy m_proxyPlatform;
 
 protected:
     virtual void SetUp()
     {
         m_mockCompositor = 0;
         Platform::initialize(&m_proxyPlatform);
     }
 
     void setCompositorForTesting(WebCompositorSupportMock& mock)
     {
         ASSERT(!m_mockCompositor);
         m_mockCompositor = &mock;
     }
 };
 
 }
 
 #endif