[jdk21u-dev] RFR: 8315981: Opensource five more random Swing tests

[Goetz Lindenmaier]

I backport this for parity with 21.0.8-oracle,

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Commit messages:
 - Backport c43ebd34afeab9ece9dee05f0da184a20e487a12

Changes: https://git.openjdk.org/jdk21u-dev/pull/1539/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=1539&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8315981
  Stats: 297 lines in 5 files changed: 297 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/1539.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/1539/head:pull/1539

PR: https://git.openjdk.org/jdk21u-dev/pull/1539