Reproduced in build 060828.

To reproduce the bug:

- create a new schema;
- switch to Source view;
- add SimpleType '<xsd:simpleType></xsd:simpleType>';
- switch to Schema view;
- click on Simple Type node.

NPE:

java.lang.IndexOutOfBoundsException: Index: 1, Size: 1
	at java.util.ArrayList.RangeCheck(ArrayList.java:547)
	at java.util.ArrayList.get(ArrayList.java:322)
	at
org.netbeans.modules.xml.xam.ui.column.BasicColumnView.removeColumnsAfter(BasicColumnView.java:144)
	at
org.netbeans.modules.xml.schema.ui.basic.SchemaColumnsView.removeColumnsAfter(SchemaColumnsView.java:354)
	at
org.netbeans.modules.xml.schema.ui.basic.SchemaColumn.addDetailColumn(SchemaColumn.java:254)
	at
org.netbeans.modules.xml.schema.ui.basic.SchemaColumn.propertyChange(SchemaColumn.java:211)
	at
java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:339)
	at
java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:276)
	at org.openide.explorer.ExplorerManager$2.run(ExplorerManager.java:776)
	at org.openide.util.Mutex.doEvent(Mutex.java:1158)
	at org.openide.util.Mutex.readAccess(Mutex.java:284)
	at org.openide.explorer.ExplorerManager.fireInAWT(ExplorerManager.java:773)
	at org.openide.explorer.ExplorerManager.access$600(ExplorerManager.java:58)
	at
org.openide.explorer.ExplorerManager$1AtomicSetSelectedNodes.updateSelection(ExplorerManager.java:248)
	at
org.openide.explorer.ExplorerManager$1AtomicSetSelectedNodes.run(ExplorerManager.java:253)
	at org.openide.util.Mutex.readAccess(Mutex.java:293)
	at org.openide.explorer.ExplorerManager.setSelectedNodes(ExplorerManager.java:259)
	at org.openide.explorer.view.ListView.selectionChanged(ListView.java:406)
	at org.openide.explorer.view.ListView$Listener.valueChanged(ListView.java:1198)
	at
javax.swing.DefaultListSelectionModel.fireValueChanged(DefaultListSelectionModel.java:187)
	at
javax.swing.DefaultListSelectionModel.fireValueChanged(DefaultListSelectionModel.java:167)
	at
javax.swing.DefaultListSelectionModel.fireValueChanged(DefaultListSelectionModel.java:214)
	at
javax.swing.DefaultListSelectionModel.changeSelection(DefaultListSelectionModel.java:408)
	at
javax.swing.DefaultListSelectionModel.changeSelection(DefaultListSelectionModel.java:417)
	at
javax.swing.DefaultListSelectionModel.setSelectionInterval(DefaultListSelectionModel.java:441)
	at javax.swing.JList.setSelectionInterval(JList.java:1962)
	at
javax.swing.plaf.basic.BasicListUI$Handler.adjustSelection(BasicListUI.java:2704)
	at javax.swing.plaf.basic.BasicListUI$Handler.mousePressed(BasicListUI.java:2667)
	at java.awt.AWTEventMulticaster.mousePressed(AWTEventMulticaster.java:221)
	at java.awt.AWTEventMulticaster.mousePressed(AWTEventMulticaster.java:221)
	at java.awt.Component.processMouseEvent(Component.java:5996)
	at javax.swing.JComponent.processMouseEvent(JComponent.java:3240)
	at java.awt.Component.processEvent(Component.java:5764)
	at java.awt.Container.processEvent(Container.java:1984)
	at java.awt.Component.dispatchEventImpl(Component.java:4407)
	at java.awt.Container.dispatchEventImpl(Container.java:2042)
	at java.awt.Component.dispatchEvent(Component.java:4237)
	at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4248)
	at java.awt.LightweightDispatcher.processMouseEvent(Container.java:3909)
	at java.awt.LightweightDispatcher.dispatchEvent(Container.java:3842)
	at java.awt.Container.dispatchEventImpl(Container.java:2028)
	at java.awt.Window.dispatchEventImpl(Window.java:2405)
	at java.awt.Component.dispatchEvent(Component.java:4237)
[catch] at java.awt.EventQueue.dispatchEvent(EventQueue.java:600)
	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)