Bug 136973 Refresh problem-column name in chart builder
Description: Use flat file datasource, if change the column name in flat file, the column name will changed in data explorer but not refreshed in chart builder accordingly. Only restart Eclipse will get the correct information.
data/org.eclipse.birt.report.data.adapter/src/org/eclipse/birt/report/data/adapter/impl/DataSetMetaDataHelper.java
dataSetHandle.setCachedMetaData( StructureFactory.createCachedMetaData( ) );
			if ( rsMeta != null && rsMeta.getColumnCount( ) != 0 )
			{
				for ( int i = 1; i <= rsMeta.getColumnCount( ); i++ )
				{
					ResultSetColumn rsc = StructureFactory.createResultSetColumn( );
					rsc.setColumnName( getColumnName( rsMeta, i ) );
					rsc.setDataType( toModelDataType( rsMeta.getColumnType( i ) ) );
					rsc.setPosition( new Integer( i ) );
					dataSetHandle.getCachedMetaDataHandle( )
							.getResultSet( )
							.addItem( rsc );
				}
			}
		}
		if ( e != null )
			throw e;
		return rsMeta;
	}
	/**
	 * 
	 * @param dataSetHandle
	 * @param rsMeta
	 * @return
	 * @throws BirtException
	 */
	private boolean needsSetCachedMetaData( DataSetHandle dataSetHandle,
			IResultMetaData rsMeta ) throws BirtException
	{
		if ( dataSetHandle.getCachedMetaDataHandle( ) == null