Bug 185280 Expression Builder: category options rearrangement.
In expression builder under category, Available Column Bindings and Available Data sets should be listed together. Right now 'Available Column Bindings' is the first option and 'Available Data sets' is the last.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/BindingExpressionProvider.java
}
		else if ( handle instanceof GroupHandle )
		{
			dataSetHandle = ( (ReportItemHandle) ( (GroupHandle) handle ).getContainer( ) ).getDataSet( );
		}
	}
	protected List getCategoryList( )
	{
		List categoryList = super.getCategoryList( );
		if ( dataSetHandle != null )
		{
			categoryList.add( DATASETS );
		}
		return categoryList;
	}
	protected List getChildrenList( Object parent )
	{
		if ( DATASETS.equals( parent ) )
		{
			List dataSeList = new ArrayList( );
			dataSeList.add( dataSetHandle );
			return dataSeList;
		}
		if ( parent instanceof DataSetHandle )
		{
			try
			{
				List columnList = DataUtil.getColumnList( (DataSetHandle) parent );
				List outputList = getOutputList( (DataSetHandle) parent );
				columnList.addAll( outputList );