Bug 448445. Fix crash when there is no original node and no fixup. r+sr=bzbarsky

content/base/src/nsDocumentEncoder.cpp

@@ -271,10 +271,12 @@ nsDocumentEncoder::SerializeNodeStart(nsIDOMNode* aNode,
   nsCOMPtr<nsIDOMNode> node;
 
   // Caller didn't do fixup, so we'll do it ourselves
-  if (!aOriginalNode && mNodeFixup) {
+  if (!aOriginalNode) {
     aOriginalNode = aNode;
-    PRBool dummy;
-    mNodeFixup->FixupNode(aNode, &dummy, getter_AddRefs(node));
+    if (mNodeFixup) { 
+      PRBool dummy;
+      mNodeFixup->FixupNode(aNode, &dummy, getter_AddRefs(node));
+    }
   }
 
   // Either there was no fixed-up node,