x/tools/internal/jsonrpc2_v2: test failures with "connection reset by peer"

[bcmills]

#!watchflakes
post <- pkg == "golang.org/x/tools/internal/jsonrpc2_v2" && `connection reset by peer`

2021-05-20T18:25:17-2275bb5/darwin-amd64-10_12

--- FAIL: TestServe (0.29s)
    --- FAIL: TestServe/tcp (0.28s)
        serve_test.go:104: dial tcp 127.0.0.1:49317: connect: connection reset by peer
FAIL
FAIL	golang.org/x/tools/internal/jsonrpc2_v2	0.515s

2021-04-12T17:45:26-2140cce/openbsd-amd64-68

--- FAIL: TestIdleTimeout (0.20s)
    serve_test.go:50: conn2.Close failed with error: failed reading header line: read tcp 127.0.0.1:25126->127.0.0.1:44239: read: connection reset by peer
FAIL
FAIL	golang.org/x/tools/internal/jsonrpc2_v2	0.532s

CC @ianthehat @findleyr

[bcmills]

greplogs --dashboard -md -l -e '(?ms)connection reset by peer.*FAIL\s+golang\.org/x/tools/internal/jsonrpc2_v2' --since=2021-06-03

2021-10-04T20:57:50-db89b5a-e8a85e9/freebsd-amd64-race
2021-09-22T03:45:00-b98090b-051df0d/freebsd-386-11_4
2021-09-15T17:32:52-76d4494-6196979/freebsd-amd64-11_4
2021-09-11T04:35:30-915f620-170a72e/freebsd-amd64-11_2
2021-09-09T21:49:46-295a39b-21a4e67/openbsd-amd64-68
2021-08-03T20:45:05-2f64839-16ab7e4/illumos-amd64
2021-07-15T20:16:41-6e9046b-69728ea/openbsd-386-64

[findleyr]

I don't think we're going to make progress on root causing these, but we can perhaps add a retry.

[gopherbot]

Change https://go.dev/cl/388134 mentions this issue: internal/jsonrpc_v2: rework Connection concurrency

[gopherbot]

Change https://go.dev/cl/388598 mentions this issue: internal/jsonrpc2_v2: eliminate arbitrary timeouts in tests

[gopherbot]

Change https://go.dev/cl/388594 mentions this issue: internal/jsonrpc2_v2: clarify documentation

[gopherbot]

Change https://go.dev/cl/388597 mentions this issue: internal/jsonrpc2_v2: refactor concurrency in idleListener

[gopherbot]

Change https://go.dev/cl/388600 mentions this issue: internal/lsp/protocol: avoid replying with non-nil interface values in case of error

[gopherbot]

Change https://go.dev/cl/388775 mentions this issue: internal/jsonrpc2_v2: error out in-flight client calls when the reader breaks