RFR: 8318586: Explicitly handle upcall stub allocation failure

[Jorn Vernee]

Explicitly handle UpcallStub allocation failures by terminating. We currently might try to use the returned `nullptr` which would fail sooner or later. This patch just makes the termination explicit.

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Commit messages:
 - Merge branch 'master' into UpcallStubAllocFailure
 - remove unused import
 - add timeout
 - reduce code cache size in test
 - fix copyright header formatting
 - Explicitly handle upcall stub allocation failure

Changes: https://git.openjdk.org/jdk/pull/16311/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=16311&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8318586
  Stats: 87 lines in 4 files changed: 80 ins; 2 del; 5 mod
  Patch: https://git.openjdk.org/jdk/pull/16311.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/16311/head:pull/16311

PR: https://git.openjdk.org/jdk/pull/16311