RFR: 8341273: JVMTI is not properly hiding some continuation related methods [v5]

[Serguei Spitsyn]

> This fixes a problem in the VTMS (Virtual Thread Mount State) transition frames hiding mechanism.
> Please, see a fix description in the first comment.
> 
> Testing:
>  - Verified with new test `vthread/CheckHiddenFrames`
>  - Mach5 tiers 1-6 are passed

Serguei Spitsyn has updated the pull request incrementally with one additional commit since the last revision:

  review: moved notifyJvmtiStart/notifyJvmtiEnd calls from VirtualThread.run to the caller

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/21397/files
  - new: https://git.openjdk.org/jdk/pull/21397/files/0ad3fd7a..f8d05152

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=21397&range=04
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=21397&range=03-04

  Stats: 20 lines in 2 files changed: 0 ins; 5 del; 15 mod
  Patch: https://git.openjdk.org/jdk/pull/21397.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21397/head:pull/21397

PR: https://git.openjdk.org/jdk/pull/21397