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
/**
	 * 
	 * @param b
	 */
	private void enableSchemaComponent( boolean b )
	{
		if ( b )
		{
			this.schemaCombo.setEnabled( true );
			this.schemaLabel.setEnabled( true );
		}
		else
		{
			this.schemaCombo.removeAll( );
			this.schemaCombo.setEnabled( false );
			this.schemaLabel.setEnabled( false );
		}
	}
	/**
	 * 
	 * @param filterComboViewer
	 */
	private void setFilterComboContents( ComboViewer filterComboViewer )
	{
		if ( filterComboViewer == null )
		{
			return;
		}
		ArrayList dbTypeList = new ArrayList( );
		DbType tableType = new DbType( DbType.TABLE_TYPE,