Use obsolete language code of Indonesian

The java.lang.Locale will transform the official language code "id" to
the obsolete "in".  (new Locale("id")).getLanguageCode() returns
"in". To keep String representation and Locale compatible, we should
use the obsolete "in" as string representation.

This is exactly the same situation of Hebrew ("he" and "iw").

Bug: 6867914
Change-Id: I1a6ea6336d55cbf8a214f025aecf65308fb76140