Implements hook_user_login().
function system_user_login($edit, $account) {
$config = config('system.date');
// If the user has a NULL time zone, notify them to set a time zone.
if (!$account->timezone && $config
->get('timezone.user.configurable') && $config
->get('timezone.user.warn')) {
drupal_set_message(t('Configure your <a href="@user-edit">account time zone setting</a>.', array(
'@user-edit' => url("user/{$account->uid}/edit", array(
'query' => drupal_get_destination(),
'fragment' => 'edit-timezone',
)),
)));
}
}