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/TriggerDataComposite.java
lblSeriesParm.setLayoutData( gdLBLSeriesParm );
			lblSeriesParm.setText( Messages.getString( "TriggerDataComposite.Lbl.ValueSeriesName" ) ); 
			lblSeriesParm.setToolTipText( Messages.getString( "TriggerDataComposite.Tooltip.ParameterSeries" ) ); 
		}
		txtSeriesParm = new Text( grpParameters, SWT.BORDER );
		GridData gdTXTSeriesParm = new GridData( GridData.FILL_HORIZONTAL );
		gdTXTSeriesParm.horizontalSpan = 2;
		txtSeriesParm.setLayoutData( gdTXTSeriesParm );
		txtSeriesParm.setToolTipText( Messages.getString( "TriggerDataComposite.Tooltip.ParameterSeries" ) ); 
		populateLists( );
	}
	private void populateLists( )
	{
		String[] triggerTypes = LiteralHelper.triggerConditionSet.getDisplayNames( );
		cmbTriggerType.setItems( triggerTypes );
		cmbTriggerType.select( 0 );
		Trigger firstTrigger = null;
		for ( int i = 0; i < triggerTypes.length; i++ )
		{
			if ( triggersMap.containsKey( triggerTypes[i] ) )
			{
				Trigger trigger = (Trigger) triggersMap.get( triggerTypes[i] );
				
				if ( triggerMatrix.check( trigger ) )
				{
					cmbTriggerType.markSelection( triggerTypes[i] );
					if ( firstTrigger == null )
					{
						firstTrigger = trigger;