RFR: 8314498: [macos] Transferring File objects to Finder fails

[Alexey Ushakov]

Here is an updated version of the fix we have used in Jetbrains Runtime for quite a while. It has been tested by running  jdk_desktop tests and manually using a test case attached to this issue.
There is no reg test as I've not found a reliable way to verify file list content inside the system clipboard.

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Commit messages:
 - 8314498: [macos] Transferring File objects to Finder fails

Changes: https://git.openjdk.org/jdk/pull/20144/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=20144&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8314498
  Stats: 40 lines in 2 files changed: 39 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/20144.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/20144/head:pull/20144

PR: https://git.openjdk.org/jdk/pull/20144