[jdk21u-dev] RFR: 8354340: Open source Swing Tests - Set 6

[Satyen Subramaniam]

Backporting JDK-8354340: Open source Swing Tests - Set 6. Adds two viewport related swing 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 76dec47f00230214e9ba58714be5a3ad26f8308d

Changes: https://git.openjdk.org/jdk21u-dev/pull/2165/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=2165&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8354340
  Stats: 279 lines in 2 files changed: 279 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/2165.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/2165/head:pull/2165

PR: https://git.openjdk.org/jdk21u-dev/pull/2165