[jdk21u-dev] RFR: 8354653: Clean up and open source KeyEvent related tests (Part 4)

[Satyen Subramaniam]

Backporting JDK-8354653: Clean up and open source KeyEvent related tests (Part 4). Adds four key related event tests. Ran GHA Sanity Checks, local Tier 1 and 2, and new tests directly. Patch is clean. Backporting for parity with Oracle.

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Commit messages:
 - Backport a7128d86eac2c40dbfa79811234ab6226fb4d080

Changes: https://git.openjdk.org/jdk21u-dev/pull/2148/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=2148&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8354653
  Stats: 409 lines in 4 files changed: 409 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/2148.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/2148/head:pull/2148

PR: https://git.openjdk.org/jdk21u-dev/pull/2148