WP_Users_List_Table::extra_tablenav()
Method: Output the controls to allow user roles to be changed in bulk.
Source: wp-admin/includes/class-wp-users-list-table.php:300
restrict_manage_users
Action Hook: Fires just before the closing div containing the bulk role-change controls in the Users list table.
Source: wp-admin/includes/class-wp-users-list-table.php:330
WP_Users_List_Table
Class: Core class used to implement displaying users in a list table.
Source: wp-admin/includes/class-wp-users-list-table.php:17