- Since the `if` condition already causes the loop to `break`,
the `else` is not necessary. We wouldn't have reached the `else`
block, anyway, if the prior `if` condition passed.
- We are more likely to poll a successful chunk than finish
the request or throw an error. Thus, it is best if we go
for the optimistic route and check for the successful
case first.
This adds an internal ability to copy the HTTP/1 reason-phrase and place
it in the `http::Extensions` of a response, if it doesn't match the
canonical reason. This could be exposed in the Rust API later, but for
now it is only used by the C API.
