Assigns a user to a particular shortcut set.
$shortcut_set: An object representing the shortcut set.
$account: A user account that will be assigned to use the set.
function shortcut_set_assign_user($shortcut_set, $account) {
db_merge('shortcut_set_users')
->key(array(
'uid' => $account->uid,
))
->fields(array(
'set_name' => $shortcut_set->set_name,
))
->execute();
drupal_static_reset('shortcut_current_displayed_set');
}