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

Source/web/ContextFeaturesClientImpl.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:
  *
  *     * 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 24 matching lines @@
 
 namespace blink {
 
 class ContextFeaturesClientImpl final : public ContextFeaturesClient {
 public:
     static PassOwnPtr<ContextFeaturesClientImpl> create()
     {
         return adoptPtr(new ContextFeaturesClientImpl());
     }
 
-    virtual bool isEnabled(Document*, ContextFeatures::FeatureType, bool defaultValue) override;
-    virtual void urlDidChange(Document*) override;
+    bool isEnabled(Document*, ContextFeatures::FeatureType, bool defaultValue) override;
+    void urlDidChange(Document*) override;
 
 private:
     ContextFeaturesClientImpl() { }
 
     bool askIfIsEnabled(Document*, ContextFeatures::FeatureType, bool defaultValue);
 };
 
 } // namespace blink
 
 #endif // ContextFeaturesClientImpl_h