RFR: 8330003: Serial: Move the logic of FastEvacuateFollowersClosure to SerialHeap [v4]

[Guoxiong Li]

> Hi all,
> 
> This patch moves the content of `FastEvacuateFollowersClosure::do_void` to `SerialHeap::scan_evacuated_objs`.
> 
> Thanks for taking the time to review.
> 
> Best Regards,
> -- Guoxiong

Guoxiong Li has updated the pull request incrementally with two additional commits since the last revision:

 - Move YoungGenScanClosure. Inline oop_since_save_marks_iterate.
 - Revert.

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/18725/files
  - new: https://git.openjdk.org/jdk/pull/18725/files/e448e45a..8e90866d

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=18725&range=03
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=18725&range=02-03

  Stats: 36 lines in 6 files changed: 18 ins; 14 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/18725.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18725/head:pull/18725

PR: https://git.openjdk.org/jdk/pull/18725