List marker pseudo elements.

Source/core/layout/LayoutListItem.h

Index: Source/core/layout/LayoutListItem.h
diff --git a/Source/core/layout/LayoutListItem.h b/Source/core/layout/LayoutListItem.h
index 919f30a6e9d2c65ca1af394cb1425f5eaf5b296e..d2e536273a28b3a0bf8308c604e1d2fff4e9a178 100644
--- a/Source/core/layout/LayoutListItem.h
+++ b/Source/core/layout/LayoutListItem.h
@@ -70,6 +70,11 @@ private:
     virtual void insertedIntoTree() override;
     virtual void willBeRemovedFromTree() override;
 
+    virtual void subtreeChangedNotification() override;
+
+    virtual void addChild(LayoutObject* newChild, LayoutObject* beforeChild) override;
+    virtual void removeChild(LayoutObject*) override;
+
     virtual void paint(const PaintInfo&, const LayoutPoint&) override;
 
     virtual void layout() override;
@@ -78,7 +83,7 @@ private:
     bool updateMarkerLocation();
     void updateMarkerLocationAndInvalidateWidth();
 
-    void positionListMarker();
+    void positionListMarker(LayoutListMarker*);
 
     virtual void styleDidChange(StyleDifference, const ComputedStyle* oldStyle) override;
 
@@ -92,6 +97,7 @@ private:
     LayoutListMarker* m_marker;
     mutable int m_value;
 
+    bool m_inSubtreeChanged;
     bool m_hasExplicitValue : 1;
     mutable bool m_isValueUpToDate : 1;
     bool m_notInList : 1;