[jdk11u-dev] RFR: 8316306: Open source and convert manual Swing test

[Andrew Lu]

I backport this for parity with 11.0.25-oracle.

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Commit messages:
 - Backport d3e821838668a0ccc0ccd098336230975e27fd7c

Changes: https://git.openjdk.org/jdk11u-dev/pull/2840/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=2840&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8316306
  Stats: 81 lines in 1 file changed: 81 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/2840.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev.git pull/2840/head:pull/2840

PR: https://git.openjdk.org/jdk11u-dev/pull/2840