[jdk17u-dev] RFR: 7148092: [macosx] When Alt+down arrow key is pressed, the combobox popup does not appear.

[Goetz Lindenmaier]

A fix useful for mac in 17.

-------------

Commit messages:
 - Backport c42ef70a453690ecdccc570161fdfda58318ecc6

Changes: https://git.openjdk.org/jdk17u-dev/pull/2024/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=2024&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-7148092
  Stats: 128 lines in 3 files changed: 128 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/2024.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/2024/head:pull/2024

PR: https://git.openjdk.org/jdk17u-dev/pull/2024