[jdk11u-dev] RFR: 8307299: Move more DnD tests to open

[Andrew Lu]

I backport this for parity with 11.0.23-oracle.

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Commit messages:
 - Backport 950c5df859c373864ab4e7cf080c38bbd501e54b

Changes: https://git.openjdk.org/jdk11u-dev/pull/2540/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=2540&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8307299
  Stats: 1780 lines in 6 files changed: 1780 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/2540.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev.git pull/2540/head:pull/2540

PR: https://git.openjdk.org/jdk11u-dev/pull/2540