RFR: 8307130: Open source few Swing JMenu tests [v3]

[Damon Nguyen]

> Open source few Swing JMenu tests

Damon Nguyen has updated the pull request incrementally with one additional commit since the last revision:

  Add null check

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Changes:
  - all: https://git.openjdk.org/jdk/pull/13839/files
  - new: https://git.openjdk.org/jdk/pull/13839/files/1d2ccd19..d7dbe614

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=13839&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=13839&range=01-02

  Stats: 3 lines in 1 file changed: 2 ins; 0 del; 1 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