Git commits in Moodle 3.5.x by KietLy

commit 26872a80067b7bb8c599fd5b5cd6286ddfc857a7
Author: KietLy <Kiet.LyChan@nashtechglobal.com>
Date:   Thu, 28 Dec 2017 14:31:11 +0800
Tag:    v3.5.0-beta

MDL-60078 User tours accessibility: Tab should go back into the pop-up