Add a ZoneInfoDB.hasTimeZone API.

Allows us to query the DB without having to clone an object or
an entire strings array.

bug: 19106773
bug: 19987403

(cherry picked from commit 3bb833819dba8d530620ad6d43dc53c3fd54763b)

Change-Id: Ic100bc3bb0b985ca49a04ccf6a09306c758b78ef
2 files changed