Parser::getFunctionLang() is being deprecated. These two functions
have been identical since 7df3473cfea59df53debb7a9eefffed8a7f20fb3
in MW 1.19 (2012) and this extension already requires MW >= 1.38.
Bug: T318860
Change-Id: If5fa696e27e84a3aa1343551d7482c933da0a9b6