Add a test for constructLocaleFromString(String).

This is a follow up CL for ed65bc0c62ca99a118057db7ad54c4ccc14d52d0 [1],
which fixed special handling of a fake language code "tl".

  [1] Ica9cd2baac002c406f92331aadd7725d7424046a

Bug: 20696126
Change-Id: Ifc8bf2ff6bd617a215e4b68f6b2bf9b94e80db07
1 file changed