8341273: JVMTI is not properly hiding some continuation related methods

[sspitsyn]

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

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Progress

• [x] Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• [x] Change must not contain extraneous whitespace
• [x] Commit message must refer to an issue

Issue

• JDK-8341273: JVMTI is not properly hiding some continuation related methods (Bug - P3)

Reviewers

• Alan Bateman (@AlanBateman - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk.git pull/21397/head:pull/21397
$ git checkout pull/21397

Update a local copy of the PR:
$ git checkout pull/21397
$ git pull https://git.openjdk.org/jdk.git pull/21397/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 21397

View PR using the GUI difftool:
$ git pr show -t 21397

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk/pull/21397.diff

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