Convert json and jsonb to Codec

values.go

@@ -35,32 +35,6 @@ func convertSimpleArgument(ci *pgtype.ConnInfo, arg interface{}) (interface{}, e
 	}
 
 	switch arg := arg.(type) {
-
-	// https://github.com/jackc/pgx/issues/409 Changed JSON and JSONB to surface
-	// []byte to database/sql instead of string. But that caused problems with the
-	// simple protocol because the driver.Valuer case got taken before the
-	// pgtype.TextEncoder case. And driver.Valuer needed to be first in the usual
-	// case because of https://github.com/jackc/pgx/issues/339. So instead we
-	// special case JSON and JSONB.
-	case *pgtype.JSON:
-		buf, err := arg.EncodeText(ci, nil)
-		if err != nil {
-			return nil, err
-		}
-		if buf == nil {
-			return nil, nil
-		}
-		return string(buf), nil
-	case *pgtype.JSONB:
-		buf, err := arg.EncodeText(ci, nil)
-		if err != nil {
-			return nil, err
-		}
-		if buf == nil {
-			return nil, nil
-		}
-		return string(buf), nil
-
 	case driver.Valuer:
 		return callValuerValue(arg)
 	case pgtype.TextEncoder: