exp/types: fix linux build
exp/types: fix linux build

I don't understand why it was only broken on Linux

TBR=gri
CC=golang-dev
http://codereview.appspot.com/5479045

pombredanne/go-deleteme,dsriram/golang,dsriram/golang,apparentlymart/golang,tv42/old-go,tv42/old-go,pombredanne/go-deleteme,pombredanne/go-deleteme,gnanderson/go,gnanderson/go,tv42/old-go,dsriram/golang,pombredanne/go-deleteme,gnanderson/go,tv42/old-go,gnanderson/go,dsriram/golang,apparentlymart/golang,pombredanne/go-deleteme,tv42/old-go,pombredanne/go-deleteme,pombredanne/go-deleteme,dsriram/golang,gnanderson/go,gnanderson/go,apparentlymart/golang,apparentlymart/golang,gnanderson/go,tv42/old-go,tv42/old-go,dsriram/golang,apparentlymart/golang,dsriram/golang,apparentlymart/golang,apparentlymart/golang