[jdk17u-dev] RFR: 8283710: JVMTI: Use BitSet for object marking [v2]

[Roman Kennke]

> This is a backport of [JDK-8283710](https://bugs.openjdk.org/browse/JDK-8283710) to 17u.
> 
> There have been contextual differences around the declaration of _bitset and corresponding contextual differences in the constructor: the field _dead_objects did not exist in jdk19, but does exist in jdk17u. There also have been differences in the large block that has been removed (the whole of ObjectMarker and related code). Other than that, the backport has been clean and straightforward.
> 
> Testing:
>  - [x] tier1
>  - [x] tier2
>  - [x] serviceability/jvmti
>  - [x] vmTestbase/nsk/jvmti

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

  Fix copyright and include guards in jfrbitset.hpp

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

Changes:
  - all: https://git.openjdk.org/jdk17u-dev/pull/1602/files
  - new: https://git.openjdk.org/jdk17u-dev/pull/1602/files/28702844..770f70cd

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=1602&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=1602&range=00-01

  Stats: 4 lines in 1 file changed: 0 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/1602.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/1602/head:pull/1602

PR: https://git.openjdk.org/jdk17u-dev/pull/1602