RFR: 8306137: Open source several AWT ScrollPane related tests

[Tejesh R]

Open source few AWT ScrollPane related tests.

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Commit messages:
 - Converted test

Changes: https://git.openjdk.org/jdk/pull/13621/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=13621&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8306137
  Stats: 822 lines in 7 files changed: 822 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/13621.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/13621/head:pull/13621

PR: https://git.openjdk.org/jdk/pull/13621