net/http/httputil: allow MIME parameters when detecting SSE in ReverseProxy
This change allows httputil.ReverseProxy to detect SSE (server-sent events)
content when the response's Content-Type header includes MIME parameters,
such as "text/event-stream;charset=utf-8".
Prior to this change the value of the Content-Type header was compared
directly to the literal "text/event-stream". This caused a false-negative
which failed to set the FlushInterval correctly when MIME parameters were
present.
Change-Id: If8bb43efb78787b6519d7fe7599ca018a0da0023
GitHub-Last-Rev:
224518c5eb9686ee050c79f5f853ebacfdf6fc42
GitHub-Pull-Request: golang/go#48427
Reviewed-on: https://go-review.googlesource.com/c/go/+/350509
Trust: Alexander Rakoczy <alex@golang.org>
Trust: Damien Neil <dneil@google.com>
Run-TryBot: Alexander Rakoczy <alex@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Damien Neil <dneil@google.com>