RFR: 8306638: Open source some AWT tests related to datatransfer and Toolkit

[Jayathirth D V]

This PR open sources some tests related to AWT datatransfer and Toolkit.

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Commit messages:
 - 8306638: Open source some AWT tests related to datatransfer and Toolkit

Changes: https://git.openjdk.org/jdk/pull/13642/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=13642&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8306638
  Stats: 855 lines in 5 files changed: 855 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/13642.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/13642/head:pull/13642

PR: https://git.openjdk.org/jdk/pull/13642