Please use a title starting with the name of the affected package, or "all",
followed by a colon, followed by a short summary of the feature request.
Example: blob/gcsblob: add support for more blobbing.

Is your feature request related to a problem? Please describe.

When I try a http server, and transfer message by Transfer-Encoding: "chunked", it panic by interface conversion: *requestlog.responseStats is not http.Flusher: missing method Flush

Describe the solution you'd like

I want to add method Flush for type responseStats struct

Describe alternatives you've considered

Ues net/http rather than gocloud.dev to run http server

Additional context