Sharing, fix: connect to hooks from the correct classes

apps/files_sharing/appinfo/app.php

@@ -8,8 +8,8 @@ OCP\Util::connectHook("OC_Filesystem", "post_delete", "OC_Share", "deleteItem");
 OCP\Util::connectHook("OC_Filesystem", "post_rename", "OC_Share", "renameItem");
 OCP\Util::connectHook("OC_Filesystem", "post_write", "OC_Share", "updateItem");
 OCP\Util::connectHook('OC_User', 'post_deleteUser', 'OC_Share', 'removeUser');
-OCP\Util::connectHook('OC_User', 'post_addToGroup', 'OC_Share', 'addToGroupShare');
-OCP\Util::connectHook('OC_User', 'post_removeFromGroup', 'OC_Share', 'removeFromGroupShare');
+OCP\Util::connectHook('OC_Group', 'post_addToGroup', 'OC_Share', 'addToGroupShare');
+OCP\Util::connectHook('OC_Group', 'post_removeFromGroup', 'OC_Share', 'removeFromGroupShare');
 $dir = isset($_GET['dir']) ? $_GET['dir'] : '/';
 if ($dir != '/Shared' || OCP\Config::getAppValue('files_sharing', 'resharing', 'yes') == 'yes') {
 	OCP\Util::addscript("files_sharing", "share");