Steps To Reproduce:
1.Create a rectangle with overprint outline and overprint fill property set on.
2.Export to eps.
3.Convert eps file to pdf using GhostScript.
4.Import GhostScript pdf file.

Expected:

Overprint outline property should be added in graphics state referred by
rectangle with outline.

Actual:

When GhostScript converting eps file to pdf file, Ghostscript breaks the fill
and outline apart and 

exports separate rectangle. 
For each rectangle it creates two graphics state /R7 and /R8. 
/R7 << ../OP true >> referred by rectangle with fill, hence the overprint on
fill appears. 
/R8 << ..>> referred by rectangle with outline, hence overprint on outline is
dropped.

Overprint outline property is not added in the graphics state referred by
rectangle with outline.