<AWT Dev> [14] Review Request: 8234706 MenuPeer cleanup

[Sergey Bylokhov]

Hello.
Please review the fix for JDK 14.

Bug: https://bugs.openjdk.java.net/browse/JDK-8234706
Fix: http://cr.openjdk.java.net/~serb/8234706/webrev.00

The "java.awt.peer.MenuPeer" interface has the "addSeparator" method
which is unused by the java.awt.Menu since 1995. But we still
implement this method in all toolkits.

Also the "WMenuPeer.addItem()" method uses "itemPeer" variable
which is unused since 1996...

Both cases are cleaned. Mach5 is green.

-- 
Best regards, Sergey.