[8u20] request for approval to backport JDK-8035890: jdk8 javac -source 7 compiles test case it should not

[Jan Lahoda]

Hello,

I'd like to ask for an approval to backport fix for:
Bug: https://bugs.openjdk.java.net/browse/JDK-8035890
Backport bug: https://bugs.openjdk.java.net/browse/JDK-8037243
jdk9 fix: http://hg.openjdk.java.net/jdk9/dev/langtools/rev/2d06980994e0
Patch applies cleanly to: 
http://hg.openjdk.java.net/jdk8u/jdk8u-dev/langtools

Thanks,
    Jan