Bug 67890 [PropertiesView] Exception when entries added to properties view
bundles/org.eclipse.ui.views/src/org/eclipse/ui/views/properties/PropertySheetViewer.java
/**
     * Update the given entry (but not its children or parent)
     * 
     * @param entry
     *            the entry we will update
     * @param item
     *            the tree item for the given entry
     */
    private void updateEntry(IPropertySheetEntry entry, TreeItem item) {
        
        item.setData(entry);
        
        item.setText(0, entry.getDisplayName());
        item.setText(1, entry.getValueAsString());
        Image image = entry.getImage();
        if (item.getImage(1) != image)
            item.setImage(1, image);
        
        updatePlus(entry, item);
    }
    /**
     * Updates the "+"/"-" icon of the tree item from the given entry
     * or category.
     *
     * @param node the entry or category
     * @param item the tree item being updated
     */
    private void updatePlus(Object node, TreeItem item) {
        
        IPropertySheetEntry entry = null;