Update remaining core classes to use OVERRIDE / FINAL when needed

Source/core/fileapi/File.h

 /*
  * Copyright (C) 2008 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 17 matching lines @@
 
 #include "core/fileapi/Blob.h"
 #include "wtf/PassRefPtr.h"
 #include "wtf/text/WTFString.h"
 
 namespace WebCore {
 
 struct FileMetadata;
 class KURL;
 
-class File : public Blob {
+class File FINAL : public Blob {
 public:
     // AllContentTypes should only be used when the full path/name are trusted; otherwise, it could
     // allow arbitrary pages to determine what applications an user has installed.
     enum ContentTypeLookupPolicy {
         WellKnownContentTypes,
         AllContentTypes,
     };
 
     static PassRefPtr<File> create(const String& path, ContentTypeLookupPolicy policy = WellKnownContentTypes)
     {
@@ skipping 79 matching lines @@
     const double m_snapshotModificationTime;
 
     String m_relativePath;
 };
 
 DEFINE_TYPE_CASTS(File, Blob, blob, blob->isFile(), blob.isFile());
 
 } // namespace WebCore
 
 #endif // File_h