code: func (p *implementation) CLEmail(c context.Context, host string, changeNumber int64) (email string, err error) {
  	defer func() { err = common.TagGRPC(c, err) }()
  	changeInfo, err := p.clEmailAndProjectNoACLs(c, host, changeNumber)
  	if err != nil {
  		return
  	}
  	allowed, err := p.acls.IsAllowed(c, host, changeInfo.Project)
  	switch {
  	case err != nil:
  		return
  	case allowed:
  		email = changeInfo.GetOwner().GetEmail()
  	default:
  		err = errGRPCNotFound
  	}
  	return
  }
docs: // CLEmail implements Client interface.