os: fix TestRenameCaseDifference
Saw this failing on windows like this:
--- FAIL: TestRenameCaseDifference (2.96s)
--- FAIL: TestRenameCaseDifference/dir (1.64s)
testing.go:1226: TempDir RemoveAll cleanup: remove C:\Users\gopher\AppData\Local\Temp\1\TestRenameCaseDifferencedir1375918868\001: The process cannot access the file because it is being used by another process.
--- FAIL: TestRenameCaseDifference/file (1.32s)
testing.go:1226: TempDir RemoveAll cleanup: remove C:\Users\gopher\AppData\Local\Temp\1\TestRenameCaseDifferencefile3272269402\001: The process cannot access the file because it is being used by another process.
FAIL
The reason might be the directory fd is not closed. This may be
mitigated by retries in removeAll function from testing package,
but apparently it does not succeed all the time.
A link to the failed run which made me look into this: https://ci.chromium.org/ui/p/golang/builders/try/gotip-windows-386/
b8770439049015378129/overview
Change-Id: Ibebe94958d1aef8d1d0eca8a969675708cd27a7e
Reviewed-on: https://go-review.googlesource.com/c/go/+/527175
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Kirill Kolyshkin <kolyshkin@gmail.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Rob Pike <r@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>