RFR: 8339982: Open source several AWT Mouse tests - Batch 2

[Tejesh R]

Open source these AWT Mouse and GraphicsEnvironment tests:

java/awt/MouseClickCount/MouseClickCount.java
java/awt/MouseDragEnterExitTest/MouseDragEnterExitTest.java
java/awt/MouseDragTest/MouseDragTest.java
java/awt/OpenWinDoubleClickTest/OpenWinDoubleClickTest.java
java/awt/GraphicsEnvironment/DefaultScreenDeviceTest.java

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Commit messages:
 - Moved Graphics test
 - Open Source few Mouse Test
 - Open Source few Mouse Test

Changes: https://git.openjdk.org/jdk/pull/21126/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=21126&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8339982
  Stats: 676 lines in 6 files changed: 676 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/21126.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21126/head:pull/21126

PR: https://git.openjdk.org/jdk/pull/21126