Bug 209910 Drag the dataset from library, the resultset column number is doubled
Reproduce step: 1. Create one data set in library. 2. Drag it into a report design. 3. Open the data set editor, switch to the output column page, the result set number is doubled. I found there is something wrong in the org.eclipse.birt.report.model.api.util.CompatibilityUtil class. The method addStructures()will add structures list twice when the propHandle is not local.
data/org.eclipse.birt.report.data.adapter/src/org/eclipse/birt/report/data/adapter/impl/MetaDataPopulator.java
* 
	 * @param ds
	 * @param uniqueColumnName
	 * @param index
	 * @throws BirtException
	 */
	private static void updateModelColumn( DataSetHandle ds, String uniqueColumnName,
			int index ) throws BirtException
	{
		PropertyHandle resultSetColumns = ds.getPropertyHandle( DataSetHandle.RESULT_SET_PROP );
		if ( resultSetColumns == null )
			return;
		
		Iterator iterator = resultSetColumns.iterator( );
		while ( iterator.hasNext( ) )
		{
			ResultSetColumnHandle rsColumnHandle = (ResultSetColumnHandle) iterator.next( );
			assert rsColumnHandle.getPosition( ) != null;
			if ( rsColumnHandle.getPosition( ).intValue( ) == index )
			{
				if ( rsColumnHandle.getColumnName( ) != null
						&& !rsColumnHandle.getColumnName( )
								.equals( uniqueColumnName ) )
				{
					rsColumnHandle.setColumnName( uniqueColumnName );
				}
				break;
			}
		}
	}