スクリプトインクルード

var UserGroupUtil = Class.create();
UserGroupUtil.prototype = {
    initialize: function() {},
    getUserGroups: function(sys_id) {
		var userGroupList = [];
        var grUG = new GlideRecord('sys_user_grmember');
        grUG.addActiveQuery();
		grUG.addQuery('user', sys_id);
        grUG.query();
        while (grUG.next()) {
            userGroupList.push(grUG.group.sys_id);
        }
        return userGroupList.join(',');
    },
    type: 'UserGroupUtil'
};

javascript: 'sys_idIN' + new UserGroupUtil().getUserGroups(gs.getUserID());