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
{
			case SWT.LINE_SOLID :
				return LineStyle.SOLID_LITERAL;
			case SWT.LINE_DASH :
				return LineStyle.DASHED_LITERAL;
			case SWT.LINE_DASHDOT :
				return LineStyle.DASH_DOTTED_LITERAL;
			case SWT.LINE_DOT :
				return LineStyle.DOTTED_LITERAL;
			default :
				return null;
		}
	}
	/**
	 * Converts the specified model line style to an appropriate SWT line style
	 * constant
	 */
	private int getSWTLineStyle( LineStyle style )
	{
		if ( style.equals( LineStyle.DASHED_LITERAL ) )
		{
			return SWT.LINE_DASH;
		}
		else if ( style.equals( LineStyle.DASH_DOTTED_LITERAL ) )
		{
			return SWT.LINE_DASHDOT;
		}
		else if ( style.equals( LineStyle.DOTTED_LITERAL ) )
		{
			return SWT.LINE_DOT;