RFR: 8373714: Shenandoah: Register heuristic penalties following a degenerated GC [v3]

[Kelvin Nilsen]

> Add a triggering penalty when we execute degenerated GC cycle.

Kelvin Nilsen has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains four additional commits since the last revision:

 - Merge remote-tracking branch 'jdk/master' into add-degen-penalty
 - refactor for reviewer requests
 - remove redundant code
 - Increase heuristic penalties following degenerated GC

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/28834/files
  - new: https://git.openjdk.org/jdk/pull/28834/files/3f12ff15..f6d85fb7

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=28834&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=28834&range=01-02

  Stats: 11144 lines in 448 files changed: 7254 ins; 1520 del; 2370 mod
  Patch: https://git.openjdk.org/jdk/pull/28834.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/28834/head:pull/28834

PR: https://git.openjdk.org/jdk/pull/28834