MDL-63554 cachestore_memcached: Support for removal of context users

This issue is part of the MDL-62560 Epic.

cache/stores/memcached/classes/privacy/provider.php

@@ -18,15 +18,18 @@
  * Privacy Subsystem implementation for cachestore_memcached.
  *
  * @package    cachestore_memcached
+ * @category   privacy
  * @copyright  2018 Andrew Nicols <andrew@nicols.co.uk>
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 
 namespace cachestore_memcached\privacy;
 
 use core_privacy\local\metadata\collection;
-use core_privacy\local\request\contextlist;
 use core_privacy\local\request\approved_contextlist;
+use core_privacy\local\request\approved_userlist;
+use core_privacy\local\request\contextlist;
+use core_privacy\local\request\userlist;
 
 defined('MOODLE_INTERNAL') || die();
 
@@ -36,7 +39,10 @@
  * @copyright  2018 Andrew Nicols <andrew@nicols.co.uk>
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
-class provider implements \core_privacy\local\metadata\provider, \core_privacy\local\request\plugin\provider {
+class provider implements
+        \core_privacy\local\metadata\provider,
+        \core_privacy\local\request\plugin\provider,
+        \core_privacy\local\request\core_userlist_provider {
 
     /**
      * Returns meta data about this system.
@@ -61,6 +67,14 @@ public static function get_contexts_for_userid(int $userid) : contextlist {
         return new contextlist();
     }
 
+    /**
+     * Get the list of users who have data within a context.
+     *
+     * @param   userlist    $userlist   The userlist containing the list of users who have data in this context/plugin combination.
+     */
+    public static function get_users_in_context(userlist $userlist) {
+    }
+
     /**
      * Export all user data for the specified user, in the specified contexts.
      *
@@ -84,4 +98,12 @@ public static function delete_data_for_all_users_in_context(\context $context) {
      */
     public static function delete_data_for_user(approved_contextlist $contextlist) {
     }
+
+    /**
+     * Delete multiple users within a single context.
+     *
+     * @param   approved_userlist       $userlist The approved context and user information to delete information for.
+     */
+    public static function delete_data_for_users(approved_userlist $userlist) {
+    }
 }