net: wait longer before failing TestVariousDeadlines4Proc on windows

This is an attempt to make our slow
windows-386 builder more reliable.

R=golang-dev, dave
CC=golang-dev
https://golang.org/cl/12798045

src/pkg/net/timeout_test.go

@@ -496,7 +496,10 @@ func testVariousDeadlines(t *testing.T, maxProcs int) {
 				clientc <- copyRes{n, err, d}
 			}()
 
-			const tooLong = 2000 * time.Millisecond
+			tooLong := 2 * time.Second
+			if runtime.GOOS == "windows" {
+				tooLong = 5 * time.Second
+			}
 			select {
 			case res := <-clientc:
 				if isTimeout(res.err) {