[jdk17u-dev] RFR: 8328697: SubMenuShowTest and SwallowKeyEvents tests stabilization

[Goetz Lindenmaier]

I backport this for parity with 17.0.13-oracle.

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

Commit messages:
 - Backport 638708cad8228f62caf633015973403164675560

Changes: https://git.openjdk.org/jdk17u-dev/pull/3063/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=3063&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8328697
  Stats: 58 lines in 2 files changed: 29 ins; 27 del; 2 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/3063.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/3063/head:pull/3063

PR: https://git.openjdk.org/jdk17u-dev/pull/3063