[9] RFR: 8072602: Unpredictable timezone on Windows when OS's timezone is not found in tzmappings

[Masayoshi Okutsu]

Hi,

Could you please review the fix for 8072602? On Windows, the time zone 
detection code always used "GMT" if the Windows time zone can't be 
mapped to an Olson time zone ID. This fix is to use a custom time zone 
ID based on the GMT offset so that Java produces the same local time as 
the platform. A regression test requires to modify tzmappings. So this 
one is noreg-hard.

But report:
https://bugs.openjdk.java.net/browse/JDK-8072602
Webrev:
http://cr.openjdk.java.net/~okutsu/9/8072602/webrev.00/

Thanks,
Masayoshi