Steps to reproduce:
1) Use bundles from http://jre.us.oracle.com/java/re/javafx/8.0/prepromote/ea/b102/bundles/
2) Launch Modena sample as:
jdk1.8.0/bin/java -jar qa-samples/Modena.jar

Exception running application modena.Modena (Ubuntu example):
at com.sun.javafx.scene.control.skin.ScrollPaneSkin.access$2200(ScrollPaneSkin.java:64)
at com.sun.javafx.scene.control.skin.ScrollPaneSkin$4.requestLayout(ScrollPaneSkin.java:257)
at javafx.scene.Parent.requestParentLayout(Parent.java:885)
at javafx.scene.Parent.markDirtyLayout(Parent.java:853)
at javafx.scene.Parent.requestLayout(Parent.java:869)
at javafx.scene.layout.GridPane.requestLayout(GridPane.java:1647)
at javafx.scene.Parent.requestParentLayout(Parent.java:885)
at javafx.scene.Parent.markDirtyLayout(Parent.java:853)
at javafx.scene.Parent.requestLayout(Parent.java:869)
at javafx.scene.layout.HBox.requestLayout(HBox.java:562)
at javafx.scene.Parent.requestParentLayout(Parent.java:885)
at javafx.scene.Parent.markDirtyLayout(Parent.java:853)
at javafx.scene.Parent.requestLayout(Parent.java:869)
at javafx.scene.layout.Region$InsetsProperty.fireValueChanged(Region.java:560)
at javafx.scene.layout.Region$3.invalidated(Region.java:445)
at javafx.beans.property.ObjectPropertyBase.markInvalid(ObjectPropertyBase.java:111)
at javafx.beans.property.ObjectPropertyBase.set(ObjectPropertyBase.java:145)
at javafx.css.StyleableObjectProperty.set(StyleableObjectProperty.java:82)
at javafx.css.StyleableObjectProperty.applyStyle(StyleableObjectProperty.java:68)
at javafx.scene.CssStyleHelper.resetToInitialValues(CssStyleHelper.java:297)
at javafx.scene.CssStyleHelper.createStyleHelper(CssStyleHelper.java:179)
at javafx.scene.Node.impl_processCSS(Node.java:8658)
at javafx.scene.Parent.impl_processCSS(Parent.java:1216)
at javafx.scene.control.Control.impl_processCSS(Control.java:870)
at javafx.scene.Parent.impl_processCSS(Parent.java:1228)
at javafx.scene.Parent.impl_processCSS(Parent.java:1228)
at javafx.scene.Parent.impl_processCSS(Parent.java:1228)
at javafx.scene.Parent.impl_processCSS(Parent.java:1228)
at javafx.scene.Parent.impl_processCSS(Parent.java:1228)
at javafx.scene.control.Control.impl_processCSS(Control.java:870)
at javafx.scene.Parent.impl_processCSS(Parent.java:1228)
at javafx.scene.Parent.impl_processCSS(Parent.java:1228)
at javafx.scene.Node.processCSS(Node.java:8587)
at javafx.scene.Node.processCSS(Node.java:8578)
at javafx.scene.Node.processCSS(Node.java:8578)
at javafx.scene.Node.processCSS(Node.java:8578)
at javafx.scene.Node.processCSS(Node.java:8578)
at javafx.scene.Node.impl_processCSS(Node.java:8632)
at com.sun.javafx.scene.control.skin.LabeledSkinBase.updateChildren(LabeledSkinBase.java:604)
at com.sun.javafx.scene.control.skin.LabeledSkinBase.<init>(LabeledSkinBase.java:128)
at com.sun.javafx.scene.control.skin.LabelSkin.<init>(LabelSkin.java:39)
at javafx.scene.control.Label.createDefaultSkin(Label.java:156)
at javafx.scene.control.Control.impl_processCSS(Control.java:866)
at javafx.scene.Parent.impl_processCSS(Parent.java:1228)
at javafx.scene.control.Control.impl_processCSS(Control.java:862)
at javafx.scene.Node.processCSS(Node.java:8587)
at javafx.scene.Node.processCSS(Node.java:8578)
at javafx.scene.Node.processCSS(Node.java:8578)
at javafx.scene.Node.processCSS(Node.java:8578)
at javafx.scene.Node.processCSS(Node.java:8578)
at javafx.scene.Node.processCSS(Node.java:8578)
at javafx.scene.Node.processCSS(Node.java:8578)
at javafx.scene.Node.processCSS(Node.java:8578)
at javafx.scene.Node.processCSS(Node.java:8578)
at javafx.scene.Node.processCSS(Node.java:8578)
at javafx.scene.Node.processCSS(Node.java:8578)
at javafx.scene.Node.processCSS(Node.java:8578)
at javafx.scene.Node.processCSS(Node.java:8578)
at javafx.scene.Node.processCSS(Node.java:8578)
at javafx.scene.Node.processCSS(Node.java:8578)
at javafx.scene.Node.impl_processCSS(Node.java:8632)
at com.sun.javafx.scene.control.skin.ComboBoxBaseSkin.updateDisplayArea(ComboBoxBaseSkin.java:140)
at com.sun.javafx.scene.control.skin.ComboBoxBaseSkin.computePrefWidth(ComboBoxBaseSkin.java:173)
at javafx.scene.control.Control.computePrefWidth(Control.java:523)
at javafx.scene.Parent.prefWidth(Parent.java:905)
at javafx.scene.layout.Region.prefWidth(Region.java:1205)
at javafx.scene.layout.Region.computeChildPrefAreaWidth(Region.java:1481)
at javafx.scene.layout.HBox.getAreaWidths(HBox.java:466)
at javafx.scene.layout.HBox.computeContentWidth(HBox.java:542)
at javafx.scene.layout.HBox.computePrefWidth(HBox.java:426)
at javafx.scene.Parent.prefWidth(Parent.java:905)
at javafx.scene.layout.Region.prefWidth(Region.java:1205)
at javafx.scene.layout.Region.computeChildPrefAreaWidth(Region.java:1481)
at javafx.scene.layout.Region.getMaxAreaWidth(Region.java:1704)
at javafx.scene.layout.Region.computeMaxPrefAreaWidth(Region.java:1578)
at javafx.scene.layout.VBox.computePrefWidth(VBox.java:410)
at javafx.scene.Parent.prefWidth(Parent.java:905)
at javafx.scene.layout.Region.prefWidth(Region.java:1205)
at javafx.scene.layout.Region.computeChildPrefAreaWidth(Region.java:1481)
at javafx.scene.layout.Region.getMaxAreaWidth(Region.java:1704)
at javafx.scene.layout.Region.computeMaxPrefAreaWidth(Region.java:1582)
at javafx.scene.layout.StackPane.computePrefWidth(StackPane.java:309)
at javafx.scene.Parent.prefWidth(Parent.java:905)
at javafx.scene.layout.Region.prefWidth(Region.java:1205)
at javafx.scene.layout.Region.computeChildPrefAreaWidth(Region.java:1481)
at javafx.scene.layout.HBox.getAreaWidths(HBox.java:466)
at javafx.scene.layout.HBox.computeContentWidth(HBox.java:542)
at javafx.scene.layout.HBox.computePrefWidth(HBox.java:426)
at javafx.scene.Parent.prefWidth(Parent.java:905)
at javafx.scene.layout.Region.prefWidth(Region.java:1205)
at javafx.scene.layout.Region.computeChildPrefAreaWidth(Region.java:1481)
at javafx.scene.layout.Region.getMaxAreaWidth(Region.java:1704)
at javafx.scene.layout.Region.computeMaxPrefAreaWidth(Region.java:1578)
at javafx.scene.layout.VBox.computePrefWidth(VBox.java:410)
at javafx.scene.Parent.prefWidth(Parent.java:905)
at javafx.scene.layout.Region.prefWidth(Region.java:1205)
at javafx.scene.layout.AnchorPane.computeWidth(AnchorPane.java:274)
at javafx.scene.layout.AnchorPane.computePrefWidth(AnchorPane.java:250)
at javafx.scene.Parent.prefWidth(Parent.java:905)
at javafx.scene.layout.Region.prefWidth(Region.java:1205)
at com.sun.javafx.scene.control.skin.ScrollPaneSkin.canChangeHorizontalSBVisibility(ScrollPaneSkin.java:967)