RFR: 8353488: Open some JComboBox bugs 3 [v4]

[Alisen Chung]

> Opening some JComboBox bugs

Alisen Chung has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains six additional commits since the last revision:

 - update test check fail on EDT
 - Merge branch 'master' of https://github.com/openjdk/jdk into 2025tsb_3
 - add volatile
 - add robot keyrelease
 - update jtreg paths
 - opening tests

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Changes:
  - all: https://git.openjdk.org/jdk/pull/24767/files
  - new: https://git.openjdk.org/jdk/pull/24767/files/44b3691d..dc34a3c0

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=24767&range=03
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=24767&range=02-03

  Stats: 24562 lines in 439 files changed: 20485 ins; 2760 del; 1317 mod
  Patch: https://git.openjdk.org/jdk/pull/24767.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/24767/head:pull/24767

PR: https://git.openjdk.org/jdk/pull/24767