List marker pseudo elements.

Source/core/html/HTMLOListElement.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2010 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 90 matching lines @@
     updateDistribution();
     LayoutListItem::updateItemValuesForOrderedList(this);
 }
 
 void HTMLOListElement::recalculateItemCount()
 {
     m_itemCount = LayoutListItem::itemCountForOrderedList(this);
     m_shouldRecalculateItemCount = false;
 }
 
+void HTMLOListElement::attach(const AttachContext& context)
+{
+    HTMLElement::attach(context);
+
+    if (!RuntimeEnabledFeatures::listMarkerPseudoElementEnabled())
+        return;
+
+    if (!m_isReversed)
+        return;
+
+    // If we're looking at a reversed ordered list we have to recalculate
+    // all of the marker values after everything is inserted. This is because
+    // we built the tree top to bottom, but that means the list item with the
+    // highest value will end up with 1 and we count down from there.
+    updateItemValues();
 }
+
+}