net/http: use internal/race

Change-Id: Iaa5ded13e8ab4753e2e3d04c9fff203d854208ba
Reviewed-on: https://go-review.googlesource.com/119435Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

src/net/http/header.go

@@ -14,8 +14,6 @@ import (
 	"time"
 )
 
-var raceEnabled = false // set by race.go
-
 // A Header represents the key-value pairs in an HTTP header.
 type Header map[string][]string
 

src/net/http/header_test.go

@@ -6,6 +6,7 @@ package http
 
 import (
 	"bytes"
+	"internal/race"
 	"runtime"
 	"testing"
 	"time"
@@ -196,7 +197,7 @@ func TestHeaderWriteSubsetAllocs(t *testing.T) {
 	if testing.Short() {
 		t.Skip("skipping alloc test in short mode")
 	}
-	if raceEnabled {
+	if race.Enabled {
 		t.Skip("skipping test under race detector")
 	}
 	if runtime.GOMAXPROCS(0) > 1 {

src/net/http/race.go

-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// +build race
-
-package http
-
-func init() {
-	raceEnabled = true
-}