Follow these steps to reproduce:
1. TrafficServer cache a document which has "Etag" field in response header
2. The document expires.
3. UA sends request with "Range" field to this document.
4. TrafficServer sends request with IMS field to origin server to revalidate this document
5. Origin Server sends response which has 304 code and "Content-Range" field to TrafficServer
6. TrafficServer will generate another "Content-Range" field in RangeTransform.