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 Image schemaImage, tableImage, viewImage, 
		    dataBaseImage, columnImage;
	
	private Document doc = null;
	private SourceViewer viewer = null;
	private TreeItem rootNode = null;
	private Text searchTxt = null;
	private ComboViewer filterComboViewer = null;
	private Combo schemaCombo = null;
	private Label schemaLabel = null;
	private Tree availableDbObjectsTree = null;
	private Button identifierQuoteStringCheckBox = null; 
	private boolean isSchemaSupported = false;
	private boolean expandDbObjectsTree = false;
    private IMetaDataProvider metaDataProvider = null;
    private JdbcSQLSourceViewerConfiguration sourceViewerConfiguration = null;
	private String cachedSearchTxt = "";
	private String formerQueryTxt = "";
	private String cachedDbType = "";
	private int cachedSchemaComboIndex = -1;
	private DataSourceDesign prevDataSourceDesign;
	private DataSetDesign dataSetDesign;
	
	
	protected ArrayList schemaList;