net/http: fix request canceler leak on connection close
writeLoop goroutine closes persistConn closech in case of request body
write error which in turn finishes readLoop without removing request canceler.
Fixes #61708
Change-Id: Ib7c832a91b49bc7888a35a4fd2bd692236c04f86
GitHub-Last-Rev:
b74b9055e87121d4dc5d97a3f3ef1afe545bc92d
GitHub-Pull-Request: golang/go#62305
Reviewed-on: https://go-review.googlesource.com/c/go/+/523296
Reviewed-by: Carlos Amedee <carlos@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Damien Neil <dneil@google.com>