Don't try to marshal response on error.
Don't try to marshal response on error.

Fixes #7060

glycerine/cockroach,petermattis/cockroach,arjun4084346/cockroach,cockroachdb/cockroach,vivekmenezes/cockroach,cockroachdb/cockroach,paperstreet/cockroach,veteranlu/cockroach,paperstreet/cockroach,arjun4084346/cockroach,veteranlu/cockroach,sunya123/cockroach,arjun4084346/cockroach,glycerine/cockroach,vaibhavarora/cockroach,maxlang/cockroach,sunya123/cockroach,sunya123/cockroach,vivekmenezes/cockroach,cockroachdb/cockroach,veteranlu/cockroach,petermattis/cockroach,sunya123/cockroach,paperstreet/cockroach,maxlang/cockroach,petermattis/cockroach,sunya123/cockroach,vivekmenezes/cockroach,paperstreet/cockroach,petermattis/cockroach,glycerine/cockroach,vaibhavarora/cockroach,veteranlu/cockroach,vaibhavarora/cockroach,maxlang/cockroach,vivekmenezes/cockroach,paperstreet/cockroach,petermattis/cockroach,glycerine/cockroach,vaibhavarora/cockroach,veteranlu/cockroach,vivekmenezes/cockroach,vivekmenezes/cockroach,arjun4084346/cockroach,paperstreet/cockroach,veteranlu/cockroach,vaibhavarora/cockroach,vivekmenezes/cockroach,arjun4084346/cockroach,vivekmenezes/cockroach,arjun4084346/cockroach,glycerine/cockroach,veteranlu/cockroach,paperstreet/cockroach,maxlang/cockroach,maxlang/cockroach,vaibhavarora/cockroach,cockroachdb/cockroach,paperstreet/cockroach,sunya123/cockroach,petermattis/cockroach,petermattis/cockroach,maxlang/cockroach,petermattis/cockroach,glycerine/cockroach,vaibhavarora/cockroach,cockroachdb/cockroach,sunya123/cockroach,sunya123/cockroach,cockroachdb/cockroach,cockroachdb/cockroach,cockroachdb/cockroach,glycerine/cockroach,arjun4084346/cockroach,maxlang/cockroach,veteranlu/cockroach,glycerine/cockroach,vaibhavarora/cockroach,arjun4084346/cockroach,maxlang/cockroach