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

Source/core/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 139 matching lines @@
     // A Frame may not have been created yet, so we initialize the AtomicString
     // hash before trying to use it.
     AtomicString::init();
     initializeDefaultFontFamilies();
     m_page = page; // Page is not yet fully initialized wen constructing Settings, so keeping m_page null over initializeDefaultFontFamilies() call.
 }
 
 PassOwnPtr<Settings> Settings::create(Page* page)
 {
     return adoptPtr(new Settings(page));
-} 
+}
+
+void Settings::settingsChanged() const {
+    m_page->settingsChanged();
+}
 
 SETTINGS_SETTER_BODIES
 
 void Settings::initializeDefaultFontFamilies()
 {
     // Other platforms can set up fonts from a client, but on Mac, we want it in WebCore to share code between WebKit1 and WebKit2.
 }
 
 const AtomicString& Settings::standardFontFamily(UScriptCode script) const
 {
@@ skipping 208 matching lines @@
 {
     gUsesOverlayScrollbars = flag;
 }
 
 bool Settings::usesOverlayScrollbars()
 {
     return gUsesOverlayScrollbars;
 }
 
 } // namespace WebCore