Null out mListenerManager before we call ResetToURI and restore it, so ResetToURI doesn't Disconnect it. b=354865 r+sr=bzbarsky

content/xml/document/src/nsXMLDocument.cpp

@@ -421,6 +421,7 @@ nsXMLDocument::Load(const nsAString& aUrl, PRBool *aReturn)
   // be loaded.
   nsCOMPtr<nsIPrincipal> principal = NodePrincipal();
   nsCOMPtr<nsIEventListenerManager> elm(mListenerManager);
+  mListenerManager = nsnull;
 
   ResetToURI(uri, nsnull);