RFR: 8223056: Remove Type-Stable-Memory support for Parkers [v4]

[David Holmes]

> As per the bug report, once we ensure the calls to unpark() are guaranteed to only occur on a live thread (protected by a ThreadsListHandle) Parkers (the synchronization object underlying java.util.concurrent.LockSupport) no longer need to use type-stable-memory (TSM).
> 
> As a Parker is inherently associated with a single JavaThread, the Parker is now embedded directly in JavaThread, avoiding the need to use new/delete.
> 
> The Parker and PlatformParker classes are now simplified from a memory management perspective. I also made them NONCOPYABLE for good measure. Possibly other constraints could be applied to them such as disallowing new/delete? (Though if we go that far maybe we need a new allocation base type?).
> 
> Testing: tiers 1-3 plus additional test builds
> 
> Thanks,
> David

David Holmes has updated the pull request incrementally with one additional commit since the last revision:

  Rename PlatformParker event Handle to _ParkHandle as used in PlatformEvenbt - take 2

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Changes:
  - all: https://git.openjdk.java.net/jdk/pull/2089/files
  - new: https://git.openjdk.java.net/jdk/pull/2089/files/7a1c692c..11f1f1c6

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=2089&range=03
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=2089&range=02-03

  Stats: 7 lines in 1 file changed: 0 ins; 0 del; 7 mod
  Patch: https://git.openjdk.java.net/jdk/pull/2089.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/2089/head:pull/2089

PR: https://git.openjdk.java.net/jdk/pull/2089