net/http: TestWriteDeadlineExtendedOnNewRequest/h1 failures

[gopherbot]

#!watchflakes
default <- pkg == "net/http" && test == "TestWriteDeadlineExtendedOnNewRequest/h1"

Issue created automatically to collect these failures.

Example (log):

=== RUN   TestWriteDeadlineExtendedOnNewRequest/h1
==================
WARNING: DATA RACE
Read at 0x00c000434383 by goroutine 6899:
  testing.(*common).logDepth()
      /home/swarming/.swarming/w/ir/x/w/goroot/src/testing/testing.go:1023 +0x504
  testing.(*common).log()
      /home/swarming/.swarming/w/ir/x/w/goroot/src/testing/testing.go:1010 +0xa4
  testing.(*common).Logf()
      /home/swarming/.swarming/w/ir/x/w/goroot/src/testing/testing.go:1061 +0x6a
...
      /home/swarming/.swarming/w/ir/x/w/goroot/src/testing/testing.go:2159 +0x8be
  testing.(*M).Run()
      /home/swarming/.swarming/w/ir/x/w/goroot/src/testing/testing.go:2027 +0xf17
  net/http_test.TestMain()
      /home/swarming/.swarming/w/ir/x/w/goroot/src/net/http/main_test.go:24 +0x64
  main.main()
      _testmain.go:1225 +0x2d4
==================
    testing.go:1398: race detected during execution of test
--- FAIL: TestWriteDeadlineExtendedOnNewRequest/h1 (0.39s)

— watchflakes

[gopherbot]

Found new dashboard test flakes for:

#!watchflakes
default <- pkg == "net/http" && test == "TestWriteDeadlineExtendedOnNewRequest/h1"

2024-03-21 17:25 gotip-linux-amd64-longtest-race go@5e1e3a00 net/http.TestWriteDeadlineExtendedOnNewRequest/h1 (log)

=== RUN   TestWriteDeadlineExtendedOnNewRequest/h1
==================
WARNING: DATA RACE
Read at 0x00c000434383 by goroutine 6899:
  testing.(*common).logDepth()
      /home/swarming/.swarming/w/ir/x/w/goroot/src/testing/testing.go:1023 +0x504
  testing.(*common).log()
      /home/swarming/.swarming/w/ir/x/w/goroot/src/testing/testing.go:1010 +0xa4
  testing.(*common).Logf()
      /home/swarming/.swarming/w/ir/x/w/goroot/src/testing/testing.go:1061 +0x6a
...
      /home/swarming/.swarming/w/ir/x/w/goroot/src/testing/testing.go:2159 +0x8be
  testing.(*M).Run()
      /home/swarming/.swarming/w/ir/x/w/goroot/src/testing/testing.go:2027 +0xf17
  net/http_test.TestMain()
      /home/swarming/.swarming/w/ir/x/w/goroot/src/net/http/main_test.go:24 +0x64
  main.main()
      _testmain.go:1225 +0x2d4
==================
    testing.go:1398: race detected during execution of test
--- FAIL: TestWriteDeadlineExtendedOnNewRequest/h1 (0.39s)

— watchflakes

[cherrymui]

Dup of #66519.