Git commits in Moodle 3.11.1 by Tim Hunt

commit 46ba8d9e7011174ac19f5be8c0d9e90508f9bb89
Author: Tim Hunt <T.J.Hunt@open.ac.uk>
Date:   Tue, 29 Jun 2021 04:25:07 +0800
Tag:    v3.11.1

MDL-68003 session timeout warning: don't show in iframes

commit 784fd2857f78ea4f83326f0085e7a5c83bfba200
Author: Tim Hunt <T.J.Hunt@open.ac.uk>
Date:   Thu, 24 Jun 2021 18:42:33 +0800
Tag:    v3.11.1

MDL-72010 quiz: prevent session timeouts during attempts

commit 54197c12d296de6b0a15bc2bae5934b2a16ca6a4
Author: Tim Hunt <T.J.Hunt@open.ac.uk>
Date:   Tue, 22 Jun 2021 21:11:22 +0800
Tag:    v3.11.1

MDL-71991 files: check return value of rename when writing files

commit 490b59a7b371ec5ce04c291da4eb40a0a3a52b75
Author: Tim Hunt <T.J.Hunt@open.ac.uk>
Date:   Wed, 02 Jun 2021 23:06:32 +0800
Tag:    v3.11.1

MDL-71838 quiz reports: average rows calc can run out of memory