Make the CSS interface members static

Source/core/frame/LocalDOMWindow.cpp

Index: Source/core/frame/LocalDOMWindow.cpp
diff --git a/Source/core/frame/LocalDOMWindow.cpp b/Source/core/frame/LocalDOMWindow.cpp
index 6c7844051e3574eab89b829e16aee22e4641bbf2..8092a4c1db7dd35a675a8f71ae6444a63d82d70c 100644
--- a/Source/core/frame/LocalDOMWindow.cpp
+++ b/Source/core/frame/LocalDOMWindow.cpp
@@ -1312,13 +1312,6 @@ void LocalDOMWindow::cancelAnimationFrame(int id)
         d->cancelAnimationFrame(id);
 }
 
-DOMWindowCSS* LocalDOMWindow::css() const
-{
-    if (!m_css)
-        m_css = DOMWindowCSS::create();
-    return m_css.get();
-}
-
 bool LocalDOMWindow::addEventListener(const AtomicString& eventType, PassRefPtr<EventListener> prpListener, bool useCapture)
 {
     RefPtr<EventListener> listener = prpListener;
@@ -1515,7 +1508,6 @@ DEFINE_TRACE(LocalDOMWindow)
     visitor->trace(m_navigator);
     visitor->trace(m_media);
     visitor->trace(m_applicationCache);
-    visitor->trace(m_css);
     visitor->trace(m_eventQueue);
     visitor->trace(m_postMessageTimers);
     HeapSupplementable<LocalDOMWindow>::trace(visitor);