message: Only read *.pbtxt files in api_def/*_api directories when generating Go API.
diff: @@ -94,6 +94,9 @@ func updateAPIDefs(m *apiDefMap, dir string) error {
  return err
  }
  for _, file := range files {
  + if file.IsDir() || !strings.HasSuffix(file.Name(), ".pbtxt") {
  + continue
  + }
  data, err := ioutil.ReadFile(path.Join(dir, file.Name()))
  if err != nil {
  return fmt.Errorf("failed to read %q: %v", file.Name(), err)
  