RFR: 8375974: G1: Convert G1FullCollector to use Atomic<T> [v2]

[Thomas Schatzl]

> Hi all,
> 
>   please review this change to convert `G1FullCollector` to use `Atomic<T>`.
> 
> Testing: gha
> 
> Thanks,
>   Thomas

Thomas Schatzl has updated the pull request incrementally with one additional commit since the last revision:

  * kbarrett review

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/29342/files
  - new: https://git.openjdk.org/jdk/pull/29342/files/e7be9c41..c139f731

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=29342&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=29342&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/29342.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/29342/head:pull/29342

PR: https://git.openjdk.org/jdk/pull/29342