Deduplicate correlate variables question.

[stanilovsky evgeny]

Hi, calciters )

I am trying to figure out why DeduplicateCorrelateVariables [1] is called  
only if withExpand [2] flag is true ? Why we don`t need to deduplicate in  
appropriate case ?

[1]  
https://github.com/apache/calcite/blob/master/core/src/main/java/org/apache/calcite/sql2rel/SqlToRelConverter.java#L2881

[2]  
https://github.com/apache/calcite/blob/master/core/src/main/java/org/apache/calcite/sql2rel/SqlToRelConverter.java#L6209

Thanks !