7194902: [macosx] closed/java/awt/Button/DoubleActionEventTest/DoubleActionEventTest failed since jdk8b49
7181403: Invalid MouseEvent conversion with SwingUtilities.convertMouseEvent
Reviewed-by: malenkov, alexsch

Reviewed-by: rupashka

Reviewed-by: alexp

Reviewed-by: alexp

Reviewed-by: alexp

Reviewed-by: dholmes

Reviewed-by: rupashka

Reviewed-by: xdono

Reviewed-by: darcy, weijun

Reviewed-by: peterz

Reviewed-by: peterz

Summary: Introduce validate roots in AWT
Reviewed-by: alexp, art, dcherepanov

Reviewed-by: peterz

Summary: 2 new methods and some fields added to KeyEvent, plus hash of constants introduced
Reviewed-by: art

Summary: Removed unnecessary castings and other warnings
Reviewed-by: malenkov

Reviewed-by: peterz, alexp