RFR: 8288497: add support for JavaThread::is_gc_barrier_detached() [v2]

[Daniel D. Daugherty]

> A fix to add support for JavaThread::is_gc_barrier_detached() which allows
> us to add checks to detect failures like:
> 
>     JDK-8288139 JavaThread touches oop after GC barrier is detached
>     https://bugs.openjdk.org/browse/JDK-8288139
> 
> This fix along with the fix for JDK-8288139 has been tested in Mach5 Tier[1-8].
> There are no related failures in Mach5 Tier[1-7]; Mach5 Tier8 is still running.

Daniel D. Daugherty has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains three additional commits since the last revision:

 - Resolve some code review comments on v00.
 - Merge branch 'master' into JDK-8288497
 - 8288497: add support for JavaThread::is_gc_barrier_detached()

-------------

Changes:
  - all: https://git.openjdk.org/jdk19/pull/20/files
  - new: https://git.openjdk.org/jdk19/pull/20/files/fb181ab4..24ecdea4

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk19&pr=20&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk19&pr=20&range=00-01

  Stats: 362 lines in 27 files changed: 230 ins; 59 del; 73 mod
  Patch: https://git.openjdk.org/jdk19/pull/20.diff
  Fetch: git fetch https://git.openjdk.org/jdk19 pull/20/head:pull/20

PR: https://git.openjdk.org/jdk19/pull/20