Issue #1221: Pass the original element into

nsXMLContentSerializer::CheckElementEnd so that we can properly
determine whether it has children.

This resolves #1221

dom/base/nsIContentSerializer.h

@@ -55,6 +55,7 @@ class nsIContentSerializer : public nsISupports {
                                 nsAString& aStr) = 0;
 
   NS_IMETHOD AppendElementEnd(mozilla::dom::Element* aElement,
+                              mozilla::dom::Element* aOriginalElement,
                               nsAString& aStr) = 0;
 
   NS_IMETHOD Flush(nsAString& aStr) = 0;