RFR: 8296754: AutoCreateSharedArchive in JDK 20 is not compatible with JDK 19 [v6]

[Matias Saavedra Silva]

> The -XX:+AutoCreateSharedArchive flag was implemented in JDK 19, however, this flag doesn't work across JDK 19 and 20.
> 
> Expected: JDK 20 should recreate the specified CDS archive
> Actual: JDK 20 cannot recognize the archive file and gives up
> 
> The new field from GenericCDSFileMapHeader is now in FileMapHeader. Verified with tier 1-4 tests.

Matias Saavedra Silva 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 12 additional commits since the last revision:

 - Added newline to end of test
 - Removed unused import
 - Test now passes
 - Changed whitespace and comment
 - Adjusted whitespace
 - Added test
 - 8296754: AutoCreateSharedArchive in JDK 20 is not compatible with JDK 19
 - Merge branch 'master' of https://github.com/openjdk/jdk
 - Merge branch 'master' of https://github.com/openjdk/jdk
 - Merge branch 'master' of https://github.com/openjdk/jdk
 - ... and 2 more: https://git.openjdk.org/jdk/compare/d89288e1...66b03944

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/11148/files
  - new: https://git.openjdk.org/jdk/pull/11148/files/718b4f64..66b03944

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=11148&range=05
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=11148&range=04-05

  Stats: 44518 lines in 696 files changed: 16672 ins; 16259 del; 11587 mod
  Patch: https://git.openjdk.org/jdk/pull/11148.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/11148/head:pull/11148

PR: https://git.openjdk.org/jdk/pull/11148