RFR: 8301312: Create implementation of NSAccessibilityButton protocol

[Alexander Zuev]

Add the common base component for all the new implementing native classes Change native peer creation to use the new base component The new code will instantiate new protocol implementation  for the given role if it exists or an old one if it does not exist
Added BUTTON role implementing class

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Commit messages:
 - 8301312: Create implementation of NSAccessibilityButton protocol

Changes: https://git.openjdk.org/jfx/pull/1084/files
 Webrev: https://webrevs.openjdk.org/?repo=jfx&pr=1084&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8301312
  Stats: 361 lines in 7 files changed: 325 ins; 29 del; 7 mod
  Patch: https://git.openjdk.org/jfx/pull/1084.diff
  Fetch: git fetch https://git.openjdk.org/jfx.git pull/1084/head:pull/1084

PR: https://git.openjdk.org/jfx/pull/1084