Make caching of CountryTimeZones easier

Some usecases for CountryTimeZones will have
stronger consistency than others and can avoid I/O
for each lookup if the same country code is used.
Adding the isForCountryCode() method means the
normalization logic for country codes can be
encapsulated in CountryTimeZones rather than
spread around, and only one of the strings
being compared needs to be normalized.

Bug: 63743683
Test: vogar luni/src/test/java/libcore/libcore/util/CountryTimeZonesTest.java
Test: vogar luni/src/test/java/libcore/libcore/util/TimeZoneFinderTest.java

Change-Id: I51524a2f07d26ae694d9175ae24fecf901c7c8b8

0 files changed, 0 insertions, 0 deletions