exp/inotify: fix data race in linux tests Fixes issue 2708.
exp/inotify: fix data race in linux tests
Fixes issue 2708.

R=golang-dev, bradfitz
CC=golang-dev, mpimenov
http://codereview.appspot.com/5543060

wesolows/golang-old,firebitsbr/golang-old,wesolows/golang,wesolows/golang-old,firebitsbr/golang-old,wesolows/golang-old,firebitsbr/golang-old,firebitsbr/golang-old,wesolows/golang,firebitsbr/golang-old,wesolows/golang-old,wesolows/golang,firebitsbr/golang-old,wesolows/golang,wesolows/golang,wesolows/golang-old,wesolows/golang,wesolows/golang-old,firebitsbr/golang-old,firebitsbr/golang-old,wesolows/golang,wesolows/golang-old