RFR: 8366671: Refactor Thread::SpinAcquire and Thread::SpinRelease [v9]

[Anton Artemov]

> Hi, 
> 
> please consider the following changes:
> 
> In this PR `Thread::SpinAcquire()` and `Thread::SpinRelease()` methods are refactored into a utility class `SpinCriticalSection`. The motivation is to make it easier for developers to use this lightweight synchronization mechanism in the codebase. The two aforementioned methods were used in JFR to create short critical sections with a helper class, but that was not the case for the object monitor code. 
> 
> Tested in tiers 1 - 5.

Anton Artemov has updated the pull request incrementally with one additional commit since the last revision:

  8366671: Addressed reviewer's comments.

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/28264/files
  - new: https://git.openjdk.org/jdk/pull/28264/files/8ad139ab..4952da2c

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=28264&range=08
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=28264&range=07-08

  Stats: 65 lines in 2 files changed: 7 ins; 9 del; 49 mod
  Patch: https://git.openjdk.org/jdk/pull/28264.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/28264/head:pull/28264

PR: https://git.openjdk.org/jdk/pull/28264