Track changes to CountryTimeZones.lookupByOffsetWithBias()
API: the method now takes an extra argument: dstOffsetMillis,
which is unused in this case.
This commit also improves the parameter names to be more descriptive.
Bug: 139091367
Test: treehugger
Change-Id: I2090965640bb389ea41bde460f380f9ea8a6b176