nsIDOMXULElement* folder, const char* name)
nsIRDFResource* folderResource, const PRUnichar* name)
nsMessenger::RenameFolder(nsIRDFCompositeDataSource* db,                          nsIDOMXULElement* folder,                          const char* name){  nsresult rv = NS_ERROR_NULL_POINTER;  if (!db || !folder || !name || !*name) return rv;  nsCOMPtr<nsISupports> streamSupport;  rv = NS_NewCharInputStream(getter_AddRefs(streamSupport), name);  if (NS_SUCCEEDED(rv))  {    nsCOMPtr<nsISupportsArray> folderArray;    nsCOMPtr<nsISupportsArray> argsArray;    nsCOMPtr<nsIRDFResource> folderResource;    rv = folder->GetResource(getter_AddRefs(folderResource));    if (NS_SUCCEEDED(rv))    {      rv = NS_NewISupportsArray(getter_AddRefs(folderArray));      if (NS_FAILED(rv)) return rv;      folderArray->AppendElement(folderResource);      rv = NS_NewISupportsArray(getter_AddRefs(argsArray));      if (NS_FAILED(rv)) return rv;      argsArray->AppendElement(streamSupport);      rv = DoCommand(db, NC_RDF_RENAME, folderArray, argsArray);    }  }  return rv;}