RFR: 8335706: G1: Remove unused G1ConcurrentRefine::RemSetSamplingClosure::_cset [v2]

[Ivan Walulya]

> Trivial cleanup of unused field G1ConcurrentRefine::RemSetSamplingClosure::_cset.

Ivan Walulya has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains three commits:

 - Merge remote-tracking branch 'upstream/master' into JDK-8335706
 - reorder
 - Trivial

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

Changes: https://git.openjdk.org/jdk/pull/20035/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=20035&range=01
  Stats: 5 lines in 1 file changed: 1 ins; 2 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/20035.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/20035/head:pull/20035

PR: https://git.openjdk.org/jdk/pull/20035