RFR: 8349146: [REDO] Implement a better allocator for downcalls

[Per Minborg]

This PR is based on the work of @mernst-github and aims to implement an _internal_ thread-local 'stack' allocator, which works like a dynamically sized arena, but with reset functionality to reset the allocated size back to a certain level. The underlying memory could stay around between calls, which could improve performance.

Re-allocated segments are not zeroed between allocations.

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Commit messages:
 - Remove interface level
 - Add benchmark class with virtual executor
 - Add rudimentary documentation
 - Convert class to record and add @ForceInline
 - Refactor and add benchmark
 - Merge branch 'master' into internal-allocator
 - Change set from previous PR

Changes: https://git.openjdk.org/jdk/pull/24829/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=24829&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8349146
  Stats: 589 lines in 8 files changed: 568 ins; 15 del; 6 mod
  Patch: https://git.openjdk.org/jdk/pull/24829.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/24829/head:pull/24829

PR: https://git.openjdk.org/jdk/pull/24829