code: func (s *ProjectsService) GetBranchContent(projectName, branchID, fileID string) (string, *Response, error) {
  	u := fmt.Sprintf("projects/%s/branches/%s/files/%s/content", url.QueryEscape(projectName), url.QueryEscape(branchID), fileID)
  	return getStringResponseWithoutOptions(s.client, u)
  }
docs: // GetBranchContent gets the content of a file from the HEAD revision of a certain branch.
  // The content is returned as base64 encoded string.
  //
  // Gerrit API docs: https://gerrit-review.googlesource.com/Documentation/rest-api-projects.html#get-content