RFR: 8339836: Open source several AWT Mouse tests - Batch 1

[Tejesh R]

Open source these AWT Mouse tests:

java/awt/Mouse/MouseEnterExitTest.java
java/awt/Mouse/MouseEnterExitTest2.java
java/awt/Mouse/MousePressedTest.java
java/awt/Mouse/MouseEnterExitTest4.java
java/awt/Mouse/MouseEnterExitTest3.java

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Commit messages:
 - jtreg updates
 - Open Source few Mouse Test

Changes: https://git.openjdk.org/jdk/pull/21124/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=21124&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8339836
  Stats: 607 lines in 5 files changed: 607 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/21124.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21124/head:pull/21124

PR: https://git.openjdk.org/jdk/pull/21124