shares connections when hosts share both IP addresses and certificates, such as `squareup.com`
    and `www.squareup.com`. If a server refuses such sharing it will return HTTP 421 and OkHttp will
    automatically retry on an unshared connection.
 *  Fix: Don't crash if a TLS tunnel's response body is truncated.
 *  Fix: Don't track unusable routes beyond their usefulness. We had a bug where we could track