Git commits in Moodle 3.7.6 by Mikhail Golenkov

commit ae0d7f7089a9b3918beaf75d5e37360e20036233
Author: Mikhail Golenkov <mikhailgolenkov@catalyst-au.net>
Date:   Sun, 26 Apr 2020 08:56:03 +0800
Tag:    v3.7.6

MDL-67540 quiz: Start transaction before selecting existing slots.

commit e061d00010a4f90a41729a5f96597e9ee9de5b60
Author: Mikhail Golenkov <mikhailgolenkov@catalyst-au.net>
Date:   Thu, 02 Apr 2020 07:49:36 +0800
Tag:    v3.7.6

MDL-65700 javascript: Add MDN and URL polyfills.

commit f8c7167b5d6101d2d5be7fdca7385f2f24a7a760
Author: Mikhail Golenkov <mikhailgolenkov@catalyst-au.net>
Date:   Thu, 26 Mar 2020 14:33:36 +0800
Tag:    v3.7.6

MDL-68223 assign: Fix selection of comment text.