Missing {} around table name in Admin/User/User

Visiting admin/user/user when you're using a table prefix in your database, you get the following warning:

user warning: Table 'drupal.users' doesn't exist query: SELECT COUNT(DISTINCT u.uid) FROM users u LEFT JOIN users_roles ur ON u.uid = ur.uid WHERE u.uid != 0 in user.admin.inc on line XXX.

This is because it doesn't put the {} around the table name. The attached patch will fix it.