Git commits in Moodle 3.7.3 by Tim Schroeder

commit c91312545db282a55d51d3ad7fdcbfaa825969c5
Author: Tim Schroeder <t.schroeder@itc.rwth-aachen.de>
Date:   Mon, 23 Sep 2019 19:29:39 +0800
Tag:    v3.7.3

MDL-66542 lib: Fix quote escaping in JS quote helper