RFR: 8350316: Create implementation of NSAccessibilityProgressIndicator protocol

[Alexander Zuev]

Initial implementation. In order to implement progress indicator the group accessibility protocol has to be implemented too so this is also a fix for 8351773. There are commented out sections that can be used to verify the functionality of the code since it has to behave exactly in the same way as the code without the fix. After review is done i will remove the debug output.

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Commit messages:
 - 8350316: Create implementation of NSAccessibilityProgressIndicator protocol

Changes: https://git.openjdk.org/jfx/pull/1796/files
  Webrev: https://webrevs.openjdk.org/?repo=jfx&pr=1796&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8350316
  Stats: 193 lines in 5 files changed: 192 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jfx/pull/1796.diff
  Fetch: git fetch https://git.openjdk.org/jfx.git pull/1796/head:pull/1796

PR: https://git.openjdk.org/jfx/pull/1796