RFR: 8306466: Open source more AWT Drag & Drop related tests [v3]

[Damon Nguyen]

> This PR open sources a few more AWT DnD related tests

Damon Nguyen has updated the pull request incrementally with one additional commit since the last revision:

  Fix review comments

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Changes:
  - all: https://git.openjdk.org/jdk/pull/13653/files
  - new: https://git.openjdk.org/jdk/pull/13653/files/5435c254..0e388731

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=13653&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=13653&range=01-02

  Stats: 35 lines in 6 files changed: 11 ins; 1 del; 23 mod
  Patch: https://git.openjdk.org/jdk/pull/13653.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/13653/head:pull/13653

PR: https://git.openjdk.org/jdk/pull/13653