RFR: 8306941: Open source several datatransfer and dnd AWT tests

[Alexander Zvegintsev]

Open sourcing few more tests:


java/awt/datatransfer/MimeFormatsTest/MimeFormatsTest.java
java/awt/datatransfer/RemoveFlavorListenerTest/RemoveFlavorListenerTest.java
java/awt/dnd/AutoscrollStopTest/AutoscrollStopTest.java
java/awt/dnd/ButtonReleaseTest/ButtonReleaseTest.java 


Testing looks good.

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Commit messages:
 - initial

Changes: https://git.openjdk.org/jdk/pull/13836/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=13836&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8306941
  Stats: 831 lines in 4 files changed: 831 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/13836.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/13836/head:pull/13836

PR: https://git.openjdk.org/jdk/pull/13836