Having this test fail, as it does reliably for me,
makes working frustrating. Disable it for now,
until we can diagnose the issue.

Update issue #8859.

Change-Id: I9dda30d60793e7a51f48f445c78ccb158068cc25
Reviewed-on: https://go-review.googlesource.com/6381Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>