RFR: JDK-8315731: Open source several Swing Text related tests

[Harshitha Onkar]

Open sourcing the following tests -

1. javax/swing/text/CompositeView/4398059/bug4398059.java
2. javax/swing/text/DefaultCaret/4197894/bug4197894.java
3. javax/swing/text/DefaultCaret/4203175/bug4203175.java
4. javax/swing/text/DefaultEditorKit/4265242/bug4265242.java
5. javax/swing/text/DefaultStyledDocument/4472852/bug4472852.java

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Commit messages:
 - Swing test changes

Changes: https://git.openjdk.org/jdk/pull/15693/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=15693&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8315731
  Stats: 473 lines in 5 files changed: 473 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/15693.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/15693/head:pull/15693

PR: https://git.openjdk.org/jdk/pull/15693