Bug 201042 [Accessibility]Chart scritp should not add by auto when click the down in keyboard[17]
Description: Chart scritp should not add by auto when click the down in keyboard[0704] Step: 1. New a chart and switch to script view. 2. Let the point on the script function selection. 3. Click the down on keyboard. Actual result: A function will add by auto. Expected result: Customer can not select the function under the second function by keyboard, and it should not be added by auto.
chart/org.eclipse.birt.chart.ui.extension/src/org/eclipse/birt/chart/ui/swt/composites/GanttLineAttributesComposite.java
private transient FillChooserComposite cmbColor = null;
	private transient Button cbVisible = null;
	private transient LineAttributes laCurrent = null;
	private transient boolean bEnableWidths = true;
	private transient boolean bEnableStyles = true;
	private transient boolean bEnableVisibility = true;
	private transient Vector vListeners = null;
	public static final int STYLE_CHANGED_EVENT = 1;
	public static final int WIDTH_CHANGED_EVENT = 2;
	public static final int COLOR_CHANGED_EVENT = 3;
	public static final int VISIBILITY_CHANGED_EVENT = 4;
	private transient boolean bEnabled = true;
	private transient boolean bEnableColor = true;
	private transient ChartWizardContext context;
	/**
	 * @param parent
	 * @param style
	 */
	public GanttLineAttributesComposite( Composite parent,
			ChartWizardContext context, int style, LineAttributes laCurrent,
			boolean bEnableWidths, boolean bEnableStyles,
			boolean bEnableVisibility )
	{
		super( parent, style );
		this.context = context;
		this.laCurrent = laCurrent;
		if ( laCurrent == null )
		{
			
			this.laCurrent = AttributeFactory.eINSTANCE.createLineAttributes( );