[8u20] Request for approval: 8033114 - The values of non-static final fields are printed for the -constants option

[Alexander Zuev]

Please approve the simple backport from jdk9.

Bug: https://bugs.openjdk.java.net/browse/JDK-8033114
Fix pushed as: 
http://hg.openjdk.java.net/jdk9/dev/langtools/rev/25222dc02281
Fix applies without an issue to 
http://hg.openjdk.java.net/jdk8u/jdk8u-dev/langtools
Webrev is available at: http://cr.openjdk.java.net/~kizune/8033975/webrev.00
There is no regression test because only the help message was changed.

/Alex