This is fallout from bug 864618: In that bug we disabled the set_language() call as it invalidly sets $LANG to the "Language" property of accountsservice, which cannot work because $LANG is a locale and "Language" is only a language name.
However, set_language() also sets the $LANG variable from ~/.dmrc, which we need for backwards compatibility and derivatives.
So what should happen is that all the code which does the `locale -a` guesswork needs to be dropped, and only these parts remain which evaluate ~/.dmrc.
This is fallout from bug 864618: In that bug we disabled the set_language() call as it invalidly sets $LANG to the "Language" property of accountsservice, which cannot work because $LANG is a locale and "Language" is only a language name.
However, set_language() also sets the $LANG variable from ~/.dmrc, which we need for backwards compatibility and derivatives.
So what should happen is that all the code which does the `locale -a` guesswork needs to be dropped, and only these parts remain which evaluate ~/.dmrc.