RFR: 8315677: Open source few swing JFileChooser and other tests [v2]

[Abhishek Kumar]

> Few closed JFileChooser and other swing tests are open sourced.

Abhishek Kumar has updated the pull request incrementally with one additional commit since the last revision:

  Review comment update

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Changes:
  - all: https://git.openjdk.org/jdk/pull/15626/files
  - new: https://git.openjdk.org/jdk/pull/15626/files/aec5fd8a..6caa246b

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=15626&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=15626&range=00-01

  Stats: 11 lines in 1 file changed: 2 ins; 0 del; 9 mod
  Patch: https://git.openjdk.org/jdk/pull/15626.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/15626/head:pull/15626

PR: https://git.openjdk.org/jdk/pull/15626