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

Source/core/page/Settings.cpp

Index: Source/core/page/Settings.cpp
diff --git a/Source/core/page/Settings.cpp b/Source/core/page/Settings.cpp
index 8d53b2baee2bd30117ac60a31d1b44316a601941..8ae4c3c6141f07172a799d71d6710f2d580a5527 100644
--- a/Source/core/page/Settings.cpp
+++ b/Source/core/page/Settings.cpp
@@ -157,7 +157,11 @@ Settings::Settings(Page* page)
 PassOwnPtr<Settings> Settings::create(Page* page)
 {
     return adoptPtr(new Settings(page));
-} 
+}
+
+void Settings::settingsChanged() const {
+    m_page->settingsChanged();
+}
 
 SETTINGS_SETTER_BODIES