*  Fix: Don't drop headers of healthy streams that raced with `GOAWAY` frames.
    This bug would cause HTTP/2 streams to occasional hang when the connection
    was shutting down.
 *  Fix: Honor `OkHttpClient.retryOnConnectionFailure()` when the response is a
    HTTP 408 Request Timeout. If retries are enabled, OkHttp will retry exactly
    once in response to a 408.
 *  Fix: Don't crash when reading the empty `HEAD` response body if it specifies