Reminder: avoid hard-coding release values in regression tests

[joe darcy]

Hello,

With the JDK 11 and JDK 12 split coming soon [1], work has begun on 
preparing the JDK 12 b01 changes to increment the version number, add 12 
as an option to javac's -source and -target options, etc.

This effort has revealed a number of regression tests which hard-code 
release values in various ways.

Please avoid this technique except when strictly necessary as it 
increases the maintenance cost of starting a new JDK release. Prefer to 
query the current release programmatically and dynamically construct 
earlier and later release values as needed.

Cheers,

-Joe

[1] http://mail.openjdk.java.net/pipermail/jdk-dev/2018-June/001462.html