RFR: 8329658: Serial: Refactor ContiguousSpace::_next_compaction_space [v4]

[Guoxiong Li]

> Hi all,
> 
> This patch removes the uncessary `ContiguousSpace::_next_compaction_space` and uses `DefNewGeneration::_promotion_failed` instead.
> 
> The tests `make test-tier1_gc` passed locally.
> 
> Thanks for taking the time to review.
> 
> Best Regards,
> -- Guoxiong

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

  Polish

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/18666/files
  - new: https://git.openjdk.org/jdk/pull/18666/files/4564baf1..f18298c6

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=18666&range=03
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=18666&range=02-03

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/18666.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18666/head:pull/18666

PR: https://git.openjdk.org/jdk/pull/18666