RFR: 8369219: JNI::RegisterNatives can cause a memory leak in CodeCache [v4]

[Francesco Andreuzzi]

> I propose to amend the check in `nmethod::is_cold` to allow not-entrant native `nmethod` instances to be collected during GC.
> 
> Passes tier1 and tier2 (fastdebug).

Francesco Andreuzzi has updated the pull request incrementally with one additional commit since the last revision:

  update foundOne

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/27742/files
  - new: https://git.openjdk.org/jdk/pull/27742/files/6bba7687..8ea13b6e

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=27742&range=03
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=27742&range=02-03

  Stats: 4 lines in 1 file changed: 4 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/27742.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/27742/head:pull/27742

PR: https://git.openjdk.org/jdk/pull/27742