Listen to post_deleteUser, post_addToGroup, and post_removeFromGroup hooks

lib/public/share.php

@@ -21,6 +21,10 @@
 
 namespace OCP;
 
+\OC_Hook::connect('OC_User', 'post_deleteUser', 'OCP\Share', 'post_deleteUser');
+\OC_Hook::connect('OC_User', 'post_addToGroup', 'OCP\Share', 'post_addToGroup');
+\OC_Hook::connect('OC_User', 'post_removeFromGroup', 'OCP\Share', 'post_removeFromGroup');
+
 /**
 * This class provides the ability for apps to share their content between users.
 * Apps must create a backend class that extends OCP\Share_Backend and register it with this class.