Author: Rossiani Wijaya
MDL-34562 accessibility compliance for chat module: Add <label> for input text and select tag
http://git.moodle.org/gw?p=moodle.git;a=commit;h=da248cbb716788cd563b67f10d214dc4d3b5c7a2
http://github.com/moodle/moodle/commit/da248cbb716788cd563b67f10d214dc4d3b5c7a2
+ 2.4 en [entermessage,mod_chat]