RFR: 8269294: Verify_before/after_young_collection should execute all verification [v2]

[Thomas Schatzl]

> Hi all,
> 
>   can I have reviews for this tiny change that moves all verification from `do_collection_pause_at_safepoint_helper()` to `verify_before/after_young_collection`?
> 
> I actually removed one call to `_hrm.verify_optional()` because it is already called in `_verifier->verify_region_sets_optional` although they are not completely equivalent as one call is `DEBUG_ONLY` and the other `NOT_PRODUCT`, but nobody is probably using the optimized build anyway. I can re-add the missing call if required.
> 
> Testing: tier1
> 
> Thanks,
>   Thomas
> 
> P.S: this is based on PR#4539, so it would be nice if it could be reviewed before this.

Thomas Schatzl 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.

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Changes:
  - all: https://git.openjdk.java.net/jdk/pull/4586/files
  - new: https://git.openjdk.java.net/jdk/pull/4586/files/14cf1aa1..14cf1aa1

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=4586&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=4586&range=00-01

  Stats: 0 lines in 0 files changed: 0 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/4586.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/4586/head:pull/4586

PR: https://git.openjdk.java.net/jdk/pull/4586