[8] Review Request: JDK-8027561 [macosx] Cleanup "may not respond to selector" warnings in native code

[Petr Pchelko]

Hello, AWT Team.

Please review the fix for the issue:
https://bugs.openjdk.java.net/browse/JDK-8027561
The fix is available at:
http://cr.openjdk.java.net/~pchelko/8027561/webrev.00/

This is a cleanup. Some native compilation warnings were fixed.

With best regards. Petr.