[release-branch.go1.13] net/http: fix panic with If-None-Match value in http.ServeContent
Updates #39817.
Fixes #39925.
Change-Id: I79f2ad7c836a8a46569f603aca583fdd526d22dc
GitHub-Last-Rev:
5b88aada219aaa2af0c7e1969ed6fa646117d9da
GitHub-Pull-Request: golang/go#39821
Reviewed-on: https://go-review.googlesource.com/c/go/+/239699
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
(cherry picked from commit
ce81a8f5e4f6c33036aa0777fabc47eeeab468dc)
Reviewed-on: https://go-review.googlesource.com/c/go/+/242077
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Marcus Weiner <marcus.weiner@gmail.com>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>