[crac] RFR: Run native CRaC checks after failed beforeCheckpoint

[Anton Kozlov]

After checkpoint failed at the Java level, it's worth to make a "dry-run" checkpoint at the native state: check file descriptors, process -XX:+CRHeapDumpOnCheckpointException, etc.

The patch also removes unused parameter of `checkpoint_restore(FdsInfo* fds)`

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Commit messages:
 - Run native checks after failed beforeCheckpoint

Changes: https://git.openjdk.java.net/crac/pull/11/files
 Webrev: https://webrevs.openjdk.java.net/?repo=crac&pr=11&range=00
  Stats: 134 lines in 7 files changed: 90 ins; 11 del; 33 mod
  Patch: https://git.openjdk.java.net/crac/pull/11.diff
  Fetch: git fetch https://git.openjdk.java.net/crac pull/11/head:pull/11

PR: https://git.openjdk.java.net/crac/pull/11