[jdk21u-dev] RFR: 8328166: Epsilon: 'EpsilonHeap::allocate_work' misuses the parameter 'size' as size in bytes

[Aleksey Shipilev]

Fixes a corner case bug in Epsilon. 

Additional testing:
 - [x] MacOS AArch64 server fastdebug, `gc/epsilon`

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Commit messages:
 - Backport 90ab52e598f74ed872fe404130d57f6596430727

Changes: https://git.openjdk.org/jdk21u-dev/pull/515/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=515&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8328166
  Stats: 4 lines in 1 file changed: 1 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/515.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/515/head:pull/515

PR: https://git.openjdk.org/jdk21u-dev/pull/515