UpdateTextInputCommands(NS_ConvertASCIItoUCS2("undo"));
UpdateTextInputCommands(NS_LITERAL_STRING("undo"));
NS_IMETHODIMP nsTextInputListener::DidRedo(nsITransactionManager *aManager,    nsITransaction *aTransaction, nsresult aRedoResult){  UpdateTextInputCommands(NS_ConvertASCIItoUCS2("undo"));  return NS_OK;}