[12] RFR: 8206886: Java does not set the default format locale correctly on mac10.13

[Naoto Sato]

Hello,

Please review the fix to the following issue:
https://bugs.openjdk.java.net/browse/JDK-8206886

The proposed changeset is located at:

http://cr.openjdk.java.net/~naoto/8206886/webrev.00/

macOS has removed the locale selection for formats since 10.12 (detail 
in the bug report). The fix intends to use the user's preferred language 
for Java's default format locale on 10.12 or later.

Naoto