Bug 153387 Database item can't be dragged and dropped onto editor field
Steps to reproduce: 1.Start up BIRT in Mac OS X; 2.File->New->Project; 3.File->New->Report Design; 4.In Data Explorer, create a New Data Source, and choose "Classic Models Inc. Sample DataBase", press "Next" and then press "finish"; 5.In Data Explorer, create a New Data Set, press "Next"; 6.In the popup window, expand the "CLASSICMODELS", select and drag a item onto the editor field at right side.
data/org.eclipse.birt.report.data.oda.jdbc.ui/src/org/eclipse/birt/report/data/oda/jdbc/ui/editors/SQLDataSetEditorPage.java
private void insertText( String text )
	{
		if ( text == null )
			return;
		StyledText textWidget = viewer.getTextWidget( );
		int selectionStart = textWidget.getSelection( ).x;
		textWidget.insert( text );
		textWidget.setSelection( selectionStart + text.length( ) );
		textWidget.setFocus( );
	}
	
	/**
	 * Creates the textual query editor 
	 * @param parent
	 */
	private void createTextualQueryComposite( Composite parent )
	{
		
        Composite composite = new Composite( parent, SWT.FILL
				| SWT.LEFT_TO_RIGHT );
        GridLayout layout = new GridLayout();
        layout.numColumns = 1;
        composite.setLayout(layout);
        
		CompositeRuler ruler = new CompositeRuler( );
		LineNumberRulerColumn lineNumbers = new LineNumberRulerColumn( );
		ruler.addDecorator( 0, lineNumbers );
		viewer = new SourceViewer( composite, ruler, SWT.H_SCROLL
				| SWT.V_SCROLL );
		sourceViewerConfiguration = new JdbcSQLSourceViewerConfiguration( this.getDataSetDesign( ) );