RFR: jsr166 integration 2019-02

[Martin Buchholz]

https://cr.openjdk.java.net/~martin/webrevs/jdk/jsr166-integration/overview.html

8195057: java/util/concurrent/CountDownLatch/Basic.java failed w/ Xcomp
https://cr.openjdk.java.net/~martin/webrevs/jdk/jsr166-integration/CountDownLatch-Basic/index.html
https://bugs.openjdk.java.net/browse/JDK-8195057

8215359: InnocuousForkJoinWorkerThread.setContextClassLoader needlessly
throws
https://cr.openjdk.java.net/~martin/webrevs/jdk/jsr166-integration/InnocuousForkJoinWorkerThread/index.html
https://bugs.openjdk.java.net/browse/JDK-8215359

8215363: needless signals in ForkJoinPool
https://cr.openjdk.java.net/~martin/webrevs/jdk/jsr166-integration/forkjoin-signals/index.html
https://bugs.openjdk.java.net/browse/JDK-8215363

Still in limbo:
8203662: remove increment of modCount from ArrayList and Vector replaceAll()
https://cr.openjdk.java.net/~martin/webrevs/jdk/jsr166-integration/replaceAll/index.html
https://bugs.openjdk.java.net/browse/JDK-8203662

8215249: Miscellaneous changes imported from jsr166 CVS 2019-02
https://cr.openjdk.java.net/~martin/webrevs/jdk/jsr166-integration/miscellaneous/index.html
https://bugs.openjdk.java.net/browse/JDK-8215249