[master] RFR: 8317352: [Lilliput] Sync with upstreaming PRs [v3]

[Roman Kennke]

> This PR syncs the Lilliput mainline repo with the changes that we are proposing in the upstreaming PRs. We have accumulated a number of diversions. Ideally, the Lilliput repo should mirror what is proposed for upstreaming, except where it integrates the upstreaming PRs in various places.
> 
> Notable changes:
> - Removed leftovers from Klass encoding removal
> - Removed heap object stats. This is currently better done by JOL.
> - Sliding GC template optimizations and fallback for G1
> - Re-enabled many tests
> 
> There is a remaining problem with CDS (the changes in archiveBuilder.cpp) which affect only Windows, which I am sorting out separately.
> 
> Testing:
>  - [x] All changed tests +UCOH
>  - [x]  All changed tests -UCOH
>  - [x] tier1 x86_64 +UCOH
>  - [x] tier1 x86_64 -UCOH
>  - [x] tier1 aarch64 +UCOH
>  - [x] tier1 aarch64 -UCOH
>  - [x] tier2 x86_64 +UCOH
>  - [x] tier2 x86_64 -UCOH
>  - [x] tier2 aarch64 +UCOH
>  - [x] tier2 aarch64 -UCOH

Roman Kennke has updated the pull request incrementally with one additional commit since the last revision:

  Restore original code

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

Changes:
  - all: https://git.openjdk.org/lilliput/pull/110/files
  - new: https://git.openjdk.org/lilliput/pull/110/files/476b3cb6..6b4d7028

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=lilliput&pr=110&range=02
 - incr: https://webrevs.openjdk.org/?repo=lilliput&pr=110&range=01-02

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/lilliput/pull/110.diff
  Fetch: git fetch https://git.openjdk.org/lilliput.git pull/110/head:pull/110

PR: https://git.openjdk.org/lilliput/pull/110