Fix getISO3Country and getISO3Language.

For backward compatibility, locales constructed with 3 letter
countries and languages must return those languages and countries
from these methods. With our strict language tag interpretation, these
were being omitted or transformed to und.

We fix this by passing only the language code (or the country code
with a fixed language) down to ICU, which will then deal with it
correctly.

bug: 15638049

Change-Id: I517a82496a2a4c36b1ae9234f7d2d4eb89b34ffe
4 files changed