[11u] RFR 8238676: jni crashes on accessing it from process exit hook

[Hohensee, Paul]

This is an Oracle 11.0.8 backport and does not apply cleanly to 11u.

Bug: https://bugs.openjdk.java.net/browse/JDK-8238676
Original changeset: https://hg.openjdk.java.net/jdk/jdk/rev/80e4a066342d
11u backport webrev: http://cr.openjdk.java.net/~phh/8238676/webrev.11u.00/

The first hunk of JtregNativeHotspot.gmk didn’t apply cleanly because 11u doesn’t include JDK-8179317<https://bugs.openjdk.java.net/browse/JDK-8179317>. The first hunk of jni.cpp didn’t apply cleanly because 11u doesn’t include JDK-8234739<https://bugs.openjdk.java.net/browse/JDK-8234739>.

Successfully runs the jtreg runtime/jni tests with the two new tests included in the patch on Linux. I don’t have ready access to a Windows box, so I’d greatly appreciate it if someone could do a quick build/test on Windows for me.

Thanks,
Paul