RFR: 8285373: Create an automated test for JDK-4702233

[Srinivas Mandalika]

Create an automated test for [JDK-4702233](https://bugs.openjdk.java.net/browse/JDK-4702233)

Several new AccessibleRole and AccessibleRelation constants are needed in those classes in the java.accessibility package. These new contants codify additions made in the GNOME, Netscape, and UNO (StarOffice) accessibility APIs.
StarOffice 6.1 and GNOME accessibility require new role, state and relation
constants in the javax.accessibility package. The existing constants are
inadequate for providing accessibility to StarOffice and GNOME applications
as required by Section 508.

Solution
--------
Define new constants in the javax.accessibility package.
AccessibleRelation
AccessibleRoles
AccessibleState
AccessibleAction
AccessibleContext

The test validates the public fields of the above AccessibleConstants.

This review is for migrating tests from a closed test suite to open.

Testing:
The test ran successfully on Mach5 with multiple runs (30) on windows-x64, linux-x64 and macos-x64.

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Commit messages:
 - 8285373: Create an automated test for JDK-4702233

Changes: https://git.openjdk.java.net/jdk/pull/8342/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=8342&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8285373
  Stats: 387 lines in 6 files changed: 387 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8342.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8342/head:pull/8342

PR: https://git.openjdk.java.net/jdk/pull/8342