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.
UI/org.eclipse.birt.report.designer.ui.editors.schematic/src/org/eclipse/birt/report/designer/internal/ui/editors/script/JSEditor.java
{
		boolean isContextChange = false;
		if ( event.getSource( ) instanceof ComboViewer )
		{
			isContextChange = JSEditor.VIEWER_CATEGORY_CONTEXT.equals( ( (ComboViewer) event.getSource( ) ).getData( JSEditor.VIEWER_CATEGORY_KEY ) );
		}
		ISelection selection = event.getSelection( );
		if ( selection != null )
		{
			Object[] sel = ( (IStructuredSelection) selection ).toArray( );
			if ( sel.length == 1 )
			{
				if ( isContextChange )
				{
					editor.cmbSubFunctionsViewer.refresh( );
					int itemCount = editor.cmbSubFunctions.getItemCount( );
					if ( itemCount > 0 )
					{
						
						editor.cmbSubFunctions.select( 0 );
					}
					editor.cmbSubFunctions.setEnabled( itemCount > 0 );
				}
				else
				{
					if ( sel[0] instanceof IMethodInfo )
					{
						IMethodInfo methodInfo = (IMethodInfo) sel[0];
						String signature = createSignature( methodInfo );
						try