stacktrace serialization cache

fix merge error

New metadata system for oldobjects built on top of simplified tagging model. Caching and serialization improvements. Flushpoint checkpoint with chunkheader contents.

8230116: Test workaround to Klass::_class_loader_data sometimes NULL problem Summary: This is a low frequency problem that we are seeing internally, this patch is mostly to rule out one theory. Reviewed-by: dcubed

8230104: JNU_IsInstanceOfByName needs const parameter Reviewed-by: alanb, rriggs Contributed-by: andrewluotechnologies@outlook.com

8229485: Add decrementExact(), incrementExact(), and negateExact() to java.lang.StrictMath Summary: three methods are added to StrictMath for consistency with Math. Tests are updated accordingly. Reviewed-by: bpb, lancea, igerasim, dfuchs, joehw, rriggs Contributed-by: Julia Boes <julia.boes@oracle.com>

8230058: Replace exception from sun.rmi.runtime.Log#getSource() with StackWalker Reviewed-by: mchung, rriggs Contributed-by: kustos@gmx.net

8230011: Consolidate duplicated classpath parsing code in classLoader.cpp Reviewed-by: ccheung, fparain

8229388: ErrorHandler and ContentHandler contain ambiguous/unfinished specification Reviewed-by: lancea

8229337: java.lang.Math class doc should be adjusted regarding -Exact methods Reviewed-by: rriggs, bpb Contributed-by: Julia Boes <julia.boes@oracle.com>

Add test for Recording::setFlushInterval

Add support for checkpoint aware flushing

Rename flush to flush-interval and add test for jcmd and -XX:StartFlightRecording

Add example apps

Fix warning

Remove race condition in TestStart