code review 6810080: runtime/race: add Windows support

src/pkg/runtime/race/race.go

Index: src/pkg/runtime/race/race.go 
=================================================================== 
--- a/src/pkg/runtime/race/race.go 
+++ b/src/pkg/runtime/race/race.go 
@@ -2,7 +2,7 @@ 
 // Use of this source code is governed by a BSD-style 
 // license that can be found in the LICENSE file. 
 
-// +build race,linux,amd64 race,darwin,amd64 
+// +build race,linux,amd64 race,darwin,amd64 race,windows,amd64 
 
 // Package race provides low-level facilities for data race detection. 
 package race