Remove Apple's unused implementation of private browsing from WebCore

Source/WebCore/storage/StorageAreaImpl.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 60 matching lines @@
     void clearForOriginDeletion();
 
     void sync();
 
 private:
     StorageAreaImpl(StorageType, PassRefPtr<SecurityOrigin>, PassRefPtr<StorageSyncManager>, unsigned quota);
     explicit StorageAreaImpl(StorageAreaImpl*);
 
     void blockUntilImportComplete() const;
     void closeDatabaseTimerFired(Timer<StorageAreaImpl>*);
-    bool disabledByPrivateBrowsingInFrame(const Frame* sourceFrame) const;
 
     void dispatchStorageEvent(const String& key, const String& oldValue, const String& newValue, Frame* sourceFrame);
 
     StorageType m_storageType;
     RefPtr<SecurityOrigin> m_securityOrigin;
     RefPtr<StorageMap> m_storageMap;
 
     RefPtr<StorageAreaSync> m_storageAreaSync;
     RefPtr<StorageSyncManager> m_storageSyncManager;
 
 #ifndef NDEBUG
     bool m_isShutdown;
 #endif
     unsigned m_accessCount;
     Timer<StorageAreaImpl> m_closeDatabaseTimer;
 };
 
 } // namespace WebCore
 
 #endif // StorageAreaImpl_h