Bug Info:
=========
TabbedPane with SCROLL_TAB_LAYOUT is not launching with gtk look and feel and it throws the NPE exception.

It causes the regression because one of the fix(6292725) in 6u2 b01.

Please find the attached java file and try to run the application with GTK look and feel.

Exception:
==========
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
        at com.sun.java.swing.plaf.gtk.GTKStyle.get(GTKStyle.java:756)
        at javax.swing.plaf.synth.SynthStyle.getInt(SynthStyle.java:952)
        at javax.swing.plaf.synth.SynthArrowButton$SynthArrowButtonUI.getPreferredSize(SynthArrowButton.java:95)
        at javax.swing.JComponent.getPreferredSize(JComponent.java:1632)
        at javax.swing.plaf.basic.BasicTabbedPaneUI$TabbedPaneScrollLayout.layoutContainer(BasicTabbedPaneUI.java:3042)
        at java.awt.Container.layout(Container.java:1432)
        at java.awt.Container.doLayout(Container.java:1421)
        at java.awt.Container.validateTree(Container.java:1519)
        at java.awt.Container.validateTree(Container.java:1526)
        at java.awt.Container.validateTree(Container.java:1526)
        at java.awt.Container.validateTree(Container.java:1526)
        at java.awt.Container.validateTree(Container.java:1526)
        at java.awt.Container.validate(Container.java:1491)
        at java.awt.Window.pack(Window.java:674)
        at JTabbedPaneSample.initComponents(JTabbedPaneSample.java:55)
        at JTabbedPaneSample.<init>(JTabbedPaneSample.java:15)
        at JTabbedPaneSample$1.run(JTabbedPaneSample.java:69)
        at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:597)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:273)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:183)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:173)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:168)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:160)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:121)
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
        at com.sun.java.swing.plaf.gtk.GTKStyle.get(GTKStyle.java:756)
        at javax.swing.plaf.synth.SynthStyle.getInt(SynthStyle.java:952)
        at javax.swing.plaf.synth.SynthArrowButton$SynthArrowButtonUI.getPreferredSize(SynthArrowButton.java:95)
        at javax.swing.JComponent.getPreferredSize(JComponent.java:1632)
        at javax.swing.plaf.basic.BasicTabbedPaneUI$TabbedPaneScrollLayout.layoutContainer(BasicTabbedPaneUI.java:3042)
        at java.awt.Container.layout(Container.java:1432)
        at java.awt.Container.doLayout(Container.java:1421)
        at java.awt.Container.validateTree(Container.java:1519)
        at java.awt.Container.validateTree(Container.java:1526)
        at java.awt.Container.validateTree(Container.java:1526)
        at java.awt.Container.validateTree(Container.java:1526)
        at java.awt.Container.validateTree(Container.java:1526)
        at java.awt.Container.validate(Container.java:1491)
        at java.awt.Window.dispatchEventImpl(Window.java:2427)
        at java.awt.Component.dispatchEvent(Component.java:4240)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:273)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:183)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:173)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:168)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:160)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:121)