RFR: 8307130: Open source few Swing JMenu tests

[Damon Nguyen]

Open source few Swing JMenu tests

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Commit messages:
 - Initial test add

Changes: https://git.openjdk.org/jdk/pull/13839/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=13839&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8307130
  Stats: 272 lines in 4 files changed: 272 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/13839.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/13839/head:pull/13839

PR: https://git.openjdk.org/jdk/pull/13839