We've had a number of internal questions about how Envoy handles trailers with chunked encoded HTTP/1.1 when transcoding back and forth between HTTP/2. I.e. how do HTTP/2 trailers get represented. Looking at the HTTP/1.1 codec implementation, it doesn't seem like it does anything useful with the trailers in StreamEncoderImpl::encodeTrailers.

I'm thinking I'm missing something here, since I thought we had reasonably complete support for HTTP/1.1 chunked encoding, but this isn't my area really. @mattklein123 I assume you know the full story here :)

CC @wlhee