RFR: 8321069: JvmtiThreadState::state_for_while_locked() returns nullptr for an attached JNI thread with a java.lang.Thread object after JDK-8319935 [v2]

[Daniel D. Daugherty]

> In the fix for the following bug:
> 
> [JDK-8319935](https://bugs.openjdk.org/browse/JDK-8319935) Ensure only one JvmtiThreadState is created for one JavaThread associated with attached native thread
> 
> JvmtiThreadState::state_for_while_locked() was changed to
> return nullptr for attaching JNI threads regardless of whether
> that JNI thread/JavaThread had a java.lang.Thread object.
> 
> We should only filter out a JavaThread that's attaching via JNI
> if it has no java.lang.Thread object.
> 
> This fix has been tested with Mach5 Tier[1-7] and there are no related test failures.
> Mach5 Tier8 is in process.
> 
> I'm going to need @jianglizhou to rerun her testing for:
> 
> [JDK-8319935](https://bugs.openjdk.org/browse/JDK-8319935) Ensure only one JvmtiThreadState is created for one JavaThread associated with attached native thread
> 
> since the test(s) for that fix are not yet integrated in the jdk/jdk repo.

Daniel D. Daugherty has updated the pull request incrementally with one additional commit since the last revision:

  dholmes CR - adjust a comment.

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/16934/files
  - new: https://git.openjdk.org/jdk/pull/16934/files/5c9eb2ec..0de1484f

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=16934&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=16934&range=00-01

  Stats: 3 lines in 1 file changed: 0 ins; 1 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/16934.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/16934/head:pull/16934

PR: https://git.openjdk.org/jdk/pull/16934