[jdk21u-dev] RFR: 8354561: Open source several swing tests batch0

[Satyen Subramaniam]

Backporting JDK-8354561: Open source several swing tests batch0. Adds three combo box tests and a test for drawing borders and titles. Ran GHA Sanity Checks and new tests directly. Patch is clean. Backporting for parity with Oracle.

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Commit messages:
 - Backport a4c5ed8144376f7ba0d2cb992da63b3e53d51f8b

Changes: https://git.openjdk.org/jdk21u-dev/pull/2305/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=2305&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8354561
  Stats: 397 lines in 4 files changed: 397 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/2305.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/2305/head:pull/2305

PR: https://git.openjdk.org/jdk21u-dev/pull/2305