runtime: usleep in TestWeakToStrongMarkTermination
There's a subtle bug in this test (big surprise): time.Sleep allocates,
so the time.Sleep(100*time.Millisecond) before unblocking gcMarkDone
might itself end up in gcMarkDone.
Work around this by using usleep here instead.
Fixes #70532.
Change-Id: I4c642ebb12f737cdb0d79ccff64b6059fc3d8b34
Reviewed-on: https://go-review.googlesource.com/c/go/+/636155 Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>