This reverts commit 794fb71d.

Reason for revert: submitted without TryBots and it broke all three race builders.

Change-Id: I80a1e566616f0ee8fa3529d4eeee04268f8a713b
Reviewed-on: https://go-review.googlesource.com/33232Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>