Thanks to Denis Denisov for noting that |host_name| could be used while
uninitialised in the resumption case.
While in the area, this change also renames |servername_done| to
something more reasonable and removes a documented value that was never
used. Additionally, the SNI ack was only sent when not resuming so
calculating whether it should be sent when processing ClientHello
extensions (which is after s->hit has been set) is superfluous.
Lastly, since SNI is only acked by servers, there's no need to worry
about the SNI callback returning NOACK in the client case.
Change-Id: Ie4ecfc347bd7afaf93b12526ff9311cc45da4df6
Reviewed-on: https://boringssl-review.googlesource.com/1700
Reviewed-by: David Benjamin <davidben@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>
ed8270a55c