RFR: 8305753: Allow JIT compilation for -Xshare:dump

[Ioi Lam]

This RFE makes it possible for the user to enable the JIT compiler during the CDS dump by specifying `-Xshare:dump -Xmixed`

By default, `-Xshare:dump` runs with `-Xint`. This maintains the previous behavior.

Which mode to use?

- Dumping in `-Xint` mode is faster when the classlist is small. `-Xint` is also required for deterministic dumping (compiler threads can change the order of the archived object).

- However, dumping in `-Xmixed` mode is faster when the class list is larger. We also need to run the compiler in Leyden so that we can generate the CDS archive and AOT code at the same time.


Tested with tiers 1-4 and builds-tier5.

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Commit messages:
 - 8305753: Enable JIT compilation for -Xshare:dump

Changes: https://git.openjdk.org/jdk/pull/16233/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=16233&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8305753
  Stats: 24 lines in 3 files changed: 14 ins; 0 del; 10 mod
  Patch: https://git.openjdk.org/jdk/pull/16233.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/16233/head:pull/16233

PR: https://git.openjdk.org/jdk/pull/16233