[jdk21u-dev] RFR: 8352684: Opensource JInternalFrame tests - series1

[Goetz Lindenmaier]

I backport this test change as it also goes to 21.0.9-oracle

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Commit messages:
 - Backport 66435c27b3e0a89e4350caf6207e36f5a9b82b7f

Changes: https://git.openjdk.org/jdk21u-dev/pull/1797/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=1797&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8352684
  Stats: 304 lines in 4 files changed: 304 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/1797.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/1797/head:pull/1797

PR: https://git.openjdk.org/jdk21u-dev/pull/1797