Bug 118780 Set alias for columns in data set but in expression builder still shows the old columns name when select the dataset.
Description: Set alias for columns in data set but in expression builder still shows the old columns name when select the dataset. Steps to reproduce: 1. New a datasource and a dataset 2. Set alias of the first column in the dataset to "column1". 3. Insert a data item and bind it to dataset. 4. In the expression builder, select the dataset and double click the first column name. Expected result: According to scr #78193 in tracker, the first column in expression build should use alias name instead of original name. Actual result: The original name of the first column was listed in the below of expression builder but the alias name appeared above as row["column1"] after double click the original name.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/ExpressionProvider.java
private static final Operator[] OPERATORS_COMPUTATIONAL = new Operator[]{
			new Operator( "+", "ExpressionProvider.Operator.Add" ), 
			new Operator( "-", "ExpressionProvider.Operator.Sub" ), 
			new Operator( "*", "ExpressionProvider.Operator.Mult" ), 
			new Operator( "/", "ExpressionProvider.Operator.Dvides" ),  
			new Operator( "++ ", "ExpressionProvider.Operator.Inc", "++" ),  
			new Operator( "-- ", "ExpressionProvider.Operator.Dec", "--" ), 
	};
	
	private static final Operator[] OPERATORS_LOGICAL = new Operator[]{
			new Operator( "&&", "ExpressionProvider.Operator.And" ),  
			new Operator( "||", "ExpressionProvider.Operator.Or" )  
	};
	private static final String DISPLAY_TEXT_ASSIGNMENT = Messages.getString( "ExpressionProvider.Operators.Assignment" ); 	
	private static final String DISPLAY_TEXT_COMPARISON = Messages.getString( "ExpressionProvider.Operators.Comparison" ); 
	private static final String DISPLAY_TEXT_COMPUTATIONAL = Messages.getString( "ExpressionProvider.Operators.Computational" ); 
	private static final String DISPLAY_TEXT_LOGICAL = Messages.getString( "ExpressionProvider.Operators.Logical" ); 
	private static final Image IMAGE_OPERATOR = getIconImage( IReportGraphicConstants.ICON_EXPRESSION_OPERATOR );
	private static final Image IMAGE_COLUMN = getIconImage( IReportGraphicConstants.ICON_DATA_COLUMN );
	private static final Image IMAGE_METHOD = getIconImage( IReportGraphicConstants.ICON_EXPRESSION_METHOD );
	private static final Image IMAGE_STATIC_METHOD = getIconImage( IReportGraphicConstants.ICON_EXPRESSION_STATIC_METHOD );
	private static final Image IMAGE_MEMBER = getIconImage( IReportGraphicConstants.ICON_EXPRESSION_MEMBER );
	private static final Image IMAGE_STATIC_MEMBER = getIconImage( IReportGraphicConstants.ICON_EXPRESSION_STATIC_MEMBER );
	public static final String OPERATORS = Messages.getString( "ExpressionProvider.Category.Operators" );  
	public static final String DATASETS = Messages.getString( "ExpressionProvider.Category.DataSets" ); 
	public static final String PARAMETERS = Messages.getString( "ExpressionProvider.Category.Parameters" ); 
	public static final String NATIVE_OBJECTS = Messages.getString( "ExpressionProvider.Category.NativeObjects" );
	public static final String BIRT_OBJECTS = Messages.getString( "ExpressionProvider.Category.BirtObjects" );
	private static final String ALL = Messages.getString( "ExpressionProvider.Label.All" ); 
	private List dataSetList;