Remove Apple's unused implementation of private browsing from WebCore

Source/WebCore/page/Settings.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2011, 2012 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 130 matching lines @@
     , m_textAutosizingFontScaleFactor(1)
 #if HACK_FORCE_TEXT_AUTOSIZING_ON_DESKTOP
     , m_textAutosizingWindowSizeOverride(320, 480)
     , m_textAutosizingEnabled(true)
 #else
     , m_textAutosizingEnabled(false)
 #endif
     SETTINGS_INITIALIZER_LIST
     , m_isJavaEnabled(false)
     , m_loadsImagesAutomatically(false)
-    , m_privateBrowsingEnabled(false)
     , m_areImagesEnabled(true)
     , m_arePluginsEnabled(false)
     , m_isScriptEnabled(false)
     , m_usesPageCache(false)
     , m_fontRenderingMode(0)
     , m_isCSSCustomFilterEnabled(false)
     , m_cssStickyPositionEnabled(true)
     , m_cssVariablesEnabled(false)
     , m_tiledBackingStoreEnabled(false)
     , m_dnsPrefetchingEnabled(false)
@@ skipping 195 matching lines @@
 
     // See comment in setLoadsImagesAutomatically.
     m_setImageLoadingSettingsTimer.startOneShot(0);
 }
 
 void Settings::setPluginsEnabled(bool arePluginsEnabled)
 {
     m_arePluginsEnabled = arePluginsEnabled;
 }
 
-void Settings::setPrivateBrowsingEnabled(bool privateBrowsingEnabled)
-{
-    if (m_privateBrowsingEnabled == privateBrowsingEnabled)
-        return;
-
-    m_privateBrowsingEnabled = privateBrowsingEnabled;
-    m_page->privateBrowsingStateChanged();
-}
-
 void Settings::setUserStyleSheetLocation(const KURL& userStyleSheetLocation)
 {
     if (m_userStyleSheetLocation == userStyleSheetLocation)
         return;
 
     m_userStyleSheetLocation = userStyleSheetLocation;
 
     m_page->userStyleSheetLocationChanged();
 }
 
@@ skipping 118 matching lines @@
 void Settings::setHiddenPageDOMTimerThrottlingEnabled(bool flag)
 {
     if (m_hiddenPageDOMTimerThrottlingEnabled == flag)
         return;
     m_hiddenPageDOMTimerThrottlingEnabled = flag;
     m_page->hiddenPageDOMTimerThrottlingStateChanged();
 }
 #endif
 
 } // namespace WebCore