hg: openjfx/9-dev/rt: 8156170: Clean up Stage and StageHelper

[chien.yang at oracle.com]

Changeset: 378a29c3fe40
Author:    ckyang
Date:      2016-05-06 17:02 -0700
URL:       http://hg.openjdk.java.net/openjfx/9-dev/rt/rev/378a29c3fe40

8156170: Clean up Stage and StageHelper
Reviewed-by: kcr

! modules/controls/src/main/java/javafx/scene/control/skin/MenuBarSkin.java
! modules/graphics/src/main/java/com/sun/javafx/robot/impl/FXRobotHelper.java
! modules/graphics/src/main/java/com/sun/javafx/stage/StageHelper.java
! modules/graphics/src/main/java/com/sun/javafx/util/Utils.java
! modules/graphics/src/main/java/javafx/stage/Stage.java