RFR: 8341072: Open source several AWT Canvas and Rectangle related tests

[Tejesh R]

Open source these AWT Canvas and Rectangle tests:
java/awt/Canvas/MultiDitherTest/MultiDitherTest.java
java/awt/Canvas/MultiGraphicsTest/MultiGraphicsTest.java
java/awt/Canvas/NoEventsLeakTest/NoEventsLeakTest.java
java/awt/Rectangle/IntersectionTest/IntersectionTest.java

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Commit messages:
 - Updated Image
 - Open source

Changes: https://git.openjdk.org/jdk/pull/21464/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=21464&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8341072
  Stats: 753 lines in 5 files changed: 753 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/21464.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21464/head:pull/21464

PR: https://git.openjdk.org/jdk/pull/21464