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

Source/core/events/SecurityPolicyViolationEvent.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:
  * 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 36 matching lines @@
     const String& referrer() const { return m_referrer; }
     const String& blockedURI() const { return m_blockedURI; }
     const String& violatedDirective() const { return m_violatedDirective; }
     const String& effectiveDirective() const { return m_effectiveDirective; }
     const String& originalPolicy() const { return m_originalPolicy; }
     const String& sourceFile() const { return m_sourceFile; }
     int lineNumber() const { return m_lineNumber; }
     int columnNumber() const { return m_columnNumber; }
     int statusCode() const { return m_statusCode; }
 
-    virtual const AtomicString& interfaceName() const override { return EventNames::SecurityPolicyViolationEvent; }
+    const AtomicString& interfaceName() const override { return EventNames::SecurityPolicyViolationEvent; }
 
     DEFINE_INLINE_VIRTUAL_TRACE() { Event::trace(visitor); }
 
 private:
     SecurityPolicyViolationEvent() { }
 
     SecurityPolicyViolationEvent(const AtomicString& type, const SecurityPolicyViolationEventInit& initializer)
         : Event(type, initializer)
         , m_lineNumber(0)
         , m_columnNumber(0)
@@ skipping 29 matching lines @@
     String m_originalPolicy;
     String m_sourceFile;
     int m_lineNumber;
     int m_columnNumber;
     int m_statusCode;
 };
 
 } // namespace blink
 
 #endif // SecurityPolicyViolationEvent_h