$window.auth2.grantOfflineAccess({redirect_uri: 'postmessage', prompt: 'select_account'}).then(handleAuth2Result);

function handleAuth2Result(response) {
  LoginService.googleUserAuth(response).then(startSession);
}

function startSession(userInfo) {
  AccountService.getProfile().then(userProfileLoaded);

  function userProfileLoaded(user_profile) {
    AccountService.getProfile().then(routeUser);
  }
}

function routeUser(){
  $state.go(INITIAL_ROUTE.route);
}