[12] RFR of JDK-8210908: Refactor java/util/prefs/PrefsSpi.sh to plain java test

[Amy Lu]

java/util/prefs/PrefsSpi.sh

Please review this patch to refactor above shell script test to java.

bug: https://bugs.openjdk.java.net/browse/JDK-8210908
webrev: http://cr.openjdk.java.net/~amlu/8210908/webrev.00/

Thanks,
Amy