[8u20] Request for approval for Nashorn test fix

[Matherey Nunez]

Hi,

Please approve the backport of following test fix:
Bug: https://bugs.openjdk.java.net/browse/JDK-8028615
jdk9-dev changeset:
http://hg.openjdk.java.net/jdk9/dev/nashorn/rev/5c906c370739

applies cleanly to 8u-dev

Thanks,
Matherey