[jdk21u-dev] RFR: 8315741: Open source few swing JFormattedTextField and JPopupMenu tests

[Goetz Lindenmaier]

I backport this for parity with 21.0.4-oracle.

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Commit messages:
 - Backport bfbc41c1f177c7a2b8e91351ac41eaffaab2d8fc

Changes: https://git.openjdk.org/jdk21u-dev/pull/387/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=387&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8315741
  Stats: 486 lines in 5 files changed: 486 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/387.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/387/head:pull/387

PR: https://git.openjdk.org/jdk21u-dev/pull/387