Add test case for bug #25883157 (ICU data lookup fallback failure).

ICU 56 uses data from CLDR 28 but the release code did not properly
handle data lookup fallback in all cases where the structure of the
CLDR 28 data depends on it.

This unit test will verify that this work-around is not removed from
Android before this problem has been fixed in ICU:

https://android.googlesource.com/platform/external/icu/+/f9ffd5b

Bug: 25883157
Change-Id: Ibf69b07b7982a462809bbdb0c97edd60f2be7a4d
1 file changed