RFR: 8294717: (bf) DirectByteBuffer constructor will leak if allocating Deallocator or Cleaner fails with OOME

[Brian Burkhalter]

Catch any `Throwable` from the `Deallocator` constructor or `Cleaner::create` and free memory to prevent a leak.

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Commit messages:
 - 8294717: (bf) DirectByteBuffer constructor will leak if allocating Deallocator or Cleaner fails with OOME

Changes: https://git.openjdk.org/jdk/pull/10588/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=10588&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8294717
  Stats: 7 lines in 1 file changed: 6 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/10588.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/10588/head:pull/10588

PR: https://git.openjdk.org/jdk/pull/10588