RFR: 8272147: Consolidate preserved marks handling with other STW collectors [v6]

[Guoxiong Li]

> Hi all,
> 
> This patch removes the class `markSweep.hpp::PreservedMark` and uses the shared `PreservedMarksSet` instead.
> 
> In order to keep the meaning of the field `_preserved_marks` in `markSweep`,
> I need to use `OopAndMarkWord` explicitly. So I move `OopAndMarkWord` out of `PreservedMarks`.
> 
> Tests:
> `hotspot:tier1` passed locally (x86 & linux).
> 
> Thanks for the review.
> 
> Best Regards,
> -- Guoxiong

Guoxiong Li has updated the pull request incrementally with one additional commit since the last revision:

  Rename 'OopAndMarkWordStack' to 'PreservedMarkStack'

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/14274/files
  - new: https://git.openjdk.org/jdk/pull/14274/files/9225c7d0..ffb7e9f1

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=14274&range=05
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=14274&range=04-05

  Stats: 3 lines in 2 files changed: 0 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/14274.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/14274/head:pull/14274

PR: https://git.openjdk.org/jdk/pull/14274