net: fix Windows build

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5505048

src/pkg/net/fd.go

@@ -377,14 +377,6 @@ func (fd *netFD) CloseWrite() error {
 	return fd.shutdown(syscall.SHUT_WR)
 }
 
-type timeoutError struct{}
-
-func (e *timeoutError) Error() string   { return "i/o timeout" }
-func (e *timeoutError) Timeout() bool   { return true }
-func (e *timeoutError) Temporary() bool { return true }
-
-var errTimeout error = &timeoutError{}
-
 func (fd *netFD) Read(p []byte) (n int, err error) {
 	if fd == nil {
 		return 0, os.EINVAL

src/pkg/net/net.go

@@ -157,6 +157,14 @@ func (e *OpError) Timeout() bool {
 	return ok && t.Timeout()
 }
 
+type timeoutError struct{}
+
+func (e *timeoutError) Error() string   { return "i/o timeout" }
+func (e *timeoutError) Timeout() bool   { return true }
+func (e *timeoutError) Temporary() bool { return true }
+
+var errTimeout error = &timeoutError{}
+
 type AddrError struct {
 	Err  string
 	Addr string