[8u20] request for approval to backport

[Jan Lahoda]

Hello,

I'd like to ask for an approval to backport fix for:
Bug: https://bugs.openjdk.java.net/browse/JDK-8028576
Backport bug: https://bugs.openjdk.java.net/browse/JDK-8031783
jdk9 fix: http://hg.openjdk.java.net/jdk9/dev/langtools/rev/c71cb4fbb329
Patch applies cleanly to: 
http://hg.openjdk.java.net/jdk8u/jdk8u-dev/langtools

Thanks,
    Jan