fix build - no netchan tests under NaCl
fix build - no netchan tests under NaCl

TBR=r
CC=golang-dev
http://codereview.appspot.com/1230042

bdwalton/debian-golang,ssrl/go,ssrl/go,tv42/old-go,h8liu/golang,pombredanne/go-deleteme,h8liu/golang,nightlyone/golang,bdwalton/debian-golang,apparentlymart/golang,tianon/debian-golang,pombredanne/go-deleteme,tv42/old-go,pombredanne/go-deleteme,h8liu/golang,bdwalton/debian-golang,ssrl/go,gnanderson/go,ssrl/go,dsriram/golang,h8liu/golang,h8liu/golang,nightlyone/golang,bdwalton/debian-golang,tianon/debian-golang,dsriram/golang,gnanderson/go,h8liu/golang,dsriram/golang,tianon/debian-golang,tv42/old-go,ssrl/go,ssrl/go,tv42/old-go,tv42/old-go,nightlyone/golang,bdwalton/debian-golang,apparentlymart/golang,dsriram/golang,apparentlymart/golang,tianon/debian-golang,nightlyone/golang,bdwalton/debian-golang,pombredanne/go-deleteme,bdwalton/debian-golang,gnanderson/go,nightlyone/golang,h8liu/golang,gnanderson/go,bdwalton/debian-golang,tianon/debian-golang,tv42/old-go,tv42/old-go,ssrl/go,gnanderson/go,apparentlymart/golang,dsriram/golang,apparentlymart/golang,dsriram/golang,nightlyone/golang,tianon/debian-golang,pombredanne/go-deleteme,apparentlymart/golang,tianon/debian-golang,pombredanne/go-deleteme,tianon/debian-golang,pombredanne/go-deleteme,dsriram/golang,gnanderson/go,nightlyone/golang,apparentlymart/golang,gnanderson/go