Enter a description of the change.

client/isolate/utils.go

 // Copyright 2015 The LUCI Authors. All rights reserved.
 // Use of this source code is governed under the Apache License, Version 2.0
 // that can be found in the LICENSE file.
 
 package isolate
 
 import (
         "fmt"
         "log"
         "path"
@@ skipping 119 matching lines @@
                         buf[n] = '/'
                         copy(buf[n+1:], targ[t0:])
                 }
                 return string(buf), nil
         }
         return targ[t0:], nil
 }
 
 // IsWindows returns True when running on the best OS there is.
 func IsWindows() bool {
+        // TODO(mcgreevy): once there is a top-level isolate directory with cmd
+        // and cli subdirs, move IsWindows into an isolate/internal package.
         return runtime.GOOS == "windows"
 }