<AWT Dev> RFR: 8256109: Create implementation for NSAccessibilityButton protocol [v2]

[Alexander Zuev]

> Creating a native peer for pushbutton accessibility role on Max OS X.
> The process of choosing of what peer to initialize is clunky so
> might be addressed in the future.

Alexander Zuev has updated the pull request incrementally with one additional commit since the last revision:

  Moved the new components implementations to the separate files.
  Changed the iitialization procedure to a class function with
  dictionary of role to class name relation.
  
  This pr is still intermittent since it uses the old style
  JNF java call syntacsis. Once fix for JDK-8257853 is integrated
  the calls needs to be converted to the new style but that is a minor
  change.

-------------

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/1549/files
  - new: https://git.openjdk.java.net/jdk/pull/1549/files/25022d24..07f20934

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=1549&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=1549&range=00-01

  Stats: 306 lines in 5 files changed: 219 ins; 78 del; 9 mod
  Patch: https://git.openjdk.java.net/jdk/pull/1549.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/1549/head:pull/1549

PR: https://git.openjdk.java.net/jdk/pull/1549