RFR: 8318586: Explicitly handle upcall stub allocation failure [v7]

[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.

Jorn Vernee has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains 14 commits:

 - Merge branch 'master' into UpcallStubAllocFailure
 - use alloc_fail_is_fatal = false on all platforms
 - add nullptr checks to other platforms
 - remove unused imports
 - remove flaky downcall stub oome test
 - remove @throws
 - Throw OOME for allocation failures
 - call fatal without holding code cache lock
 - Merge branch 'master' into UpcallStubAllocFailure
 - remove unused import
 - ... and 4 more: https://git.openjdk.org/jdk/compare/8b102ed6...0a10152b

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Changes: https://git.openjdk.org/jdk/pull/16311/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=16311&range=06
  Stats: 209 lines in 21 files changed: 189 ins; 2 del; 18 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