Lose/restore WebGL contexts if multisampling blackist status changes at runtime.

Source/core/page/Settings.h

 /*
  * Copyright (C) 2003, 2006, 2007, 2008, 2009, 2011, 2012 Apple Inc. All rights reserved.
  *           (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  *
  * 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
@@ skipping 54 matching lines @@
         static bool isDeletedValue(int value) { return value == -3; }
     };
 
     typedef HashMap<int, AtomicString, DefaultHash<int>::Hash, UScriptCodeHashTraits> ScriptFontFamilyMap;
 
     class Settings {
         WTF_MAKE_NONCOPYABLE(Settings); WTF_MAKE_FAST_ALLOCATED;
     public:
         static PassOwnPtr<Settings> create(Page*);
 
+        void settingsChanged() const;
+
         void setStandardFontFamily(const AtomicString&, UScriptCode = USCRIPT_COMMON);
         const AtomicString& standardFontFamily(UScriptCode = USCRIPT_COMMON) const;
 
         void setFixedFontFamily(const AtomicString&, UScriptCode = USCRIPT_COMMON);
         const AtomicString& fixedFontFamily(UScriptCode = USCRIPT_COMMON) const;
 
         void setSerifFontFamily(const AtomicString&, UScriptCode = USCRIPT_COMMON);
         const AtomicString& serifFontFamily(UScriptCode = USCRIPT_COMMON) const;
 
         void setSansSerifFontFamily(const AtomicString&, UScriptCode = USCRIPT_COMMON);
@@ skipping 114 matching lines @@
         Timer<Settings> m_setImageLoadingSettingsTimer;
         void imageLoadingSettingsTimerFired(Timer<Settings>*);
 
         static bool gMockScrollbarsEnabled;
         static bool gUsesOverlayScrollbars;
     };
 
 } // namespace WebCore
 
 #endif // Settings_h