Fix android.text.format.Time behavior

Fix android.text.format.Time behavior when using zic > 2014b and where
zones now have transitions close to Integer.MIN_VALUE and
Integer.MAX_VALUE. In those cases the act of adjusting for offset can
cause over/underflow and lead to -1.

This was particularly noticeable with Asia/Singapore as the last DST
transition with zic <= 2014b was in 1981 and it has a positive DST
offset. Therefore most date calculations involving times since 1981
with zic > 2014b would consider the transition at Integer.MAX_VALUE
and add the offset of 8 hours to get local time, thereby exceeding
Integer.MAX_VALUE and causing an error.

This change also fixes another bug around the offset used for times
before the first explicit transition. This was noticed while running
the new TimeTest tests with zic <= 2014b.

Testing:
atest CtsTextTestCases:android.text.format.cts.TimeTest
atest CtsLibcoreTestCases:libcore.libcore.util.ZoneInfoTest
atest CtsLibcoreTestCases:libcore.java.util.TimeZoneTest
atest FrameworksCoreTests:android.text.format.TimeTest

...with 2014b zic data and 2018e zic data. All tests pass with both.

Bug: 118835133
Test: See above
Change-Id: I0ce9eb25a783ac17f28d8dc0c63865df51bf46db

0 files changed, 0 insertions, 0 deletions