Remove SVGElementInstanceList

Source/core/svg/SVGElementInstance.h

Index: Source/core/svg/SVGElementInstance.h
diff --git a/Source/core/svg/SVGElementInstance.h b/Source/core/svg/SVGElementInstance.h
index 6021106406d8f1d823bdce00584b4c924806bddc..660b60ced786b9e50e03a4d764b703abd7cc2f10 100644
--- a/Source/core/svg/SVGElementInstance.h
+++ b/Source/core/svg/SVGElementInstance.h
@@ -34,7 +34,6 @@ void addChildNodesToDeletionQueue(GenericNode*& head, GenericNode*& tail, Generi
 
 class Document;
 class SVGElement;
-class SVGElementInstanceList;
 class SVGUseElement;
 
 // SVGElementInstance mimics Node, but without providing all its functionality
@@ -65,7 +64,6 @@ public:
     void detach();
 
     SVGElementInstance* parentNode() const { return m_parentInstance; }
-    PassRefPtr<SVGElementInstanceList> childNodes();
 
     SVGElementInstance* previousSibling() const { return m_previousSibling; }
     SVGElementInstance* nextSibling() const { return m_nextSibling; }