Use shape defined flatness for query codegen.
@@ -157,7 +157,7 @@ fn generate_list_serializer(service: &Service, shape: &Shape) -> String {
let primitive = member_shape.is_primitive();
let is_shape_flattened = match shape.flattened {
None => false,
- Some(_) => true,
+ Some(shape_defined_flatness) => shape_defined_flatness,
};
let mut parts = Vec::new();
