[crac] RFR: Fix ordering of invocation on Resources [v2]

[Radim Vansa]

> * When Context.beforeCheckpoint throws, invoke Context.afterRestore anyway (otherwise some resources stay in suspended state).
> * Handle Resource.beforeCheckpoint triggering a registration of another resource ** Do not cause deadlock when registering from another thread ** Global resource can register JDKResource
> ** JDKResource can register resource with higher priority ** Other registrations are prohibited

Radim Vansa has updated the pull request incrementally with one additional commit since the last revision:

  Fix docs & package

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Changes:
  - all: https://git.openjdk.org/crac/pull/60/files
  - new: https://git.openjdk.org/crac/pull/60/files/e801310e..fb7d4ea7

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=crac&pr=60&range=01
 - incr: https://webrevs.openjdk.org/?repo=crac&pr=60&range=00-01

  Stats: 26 lines in 7 files changed: 15 ins; 1 del; 10 mod
  Patch: https://git.openjdk.org/crac/pull/60.diff
  Fetch: git fetch https://git.openjdk.org/crac.git pull/60/head:pull/60

PR: https://git.openjdk.org/crac/pull/60