Technically, the garbage collector can take an arbitrary long time until
it finds a given value unreachable. Account for this fact in our zeroing
tests.
Updates #76586.
Change-Id: Ieaf3cec99afb9204a32524ea559c5f1a280a59e6
Reviewed-on: https://go-review.googlesource.com/c/go/+/732980 Reviewed-by: Keith Randall <khr@google.com> Reviewed-by: Cherry Mui <cherryyz@google.com> Reviewed-by: Filippo Valsorda <filippo@golang.org>
Auto-Submit: Keith Randall <khr@golang.org> Reviewed-by: Keith Randall <khr@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>