toAcl = (member) => {
    const email =
        member.replace(/^domain:|^group:|^serviceAccount:|^user:/, '');
    if (member.startsWith('group:')) {
      groups.add(email);
    }
    return email;
  }
Converts an IamPolicy object to our internal AssetAcl representation.
@param {!ee.api.Policy} result
@return {!Object}