LogDog: Add Butler stream server package.

client/logdog/butlerlib/streamclient/client_namedPipe_windows.go

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package streamclient
+
+import (
+        "errors"
+        "fmt"
+        "io"
+
+        npipe "gopkg.in/natefinch/npipe.v2"
+)
+
+// Register POSIX-only protocols.
+func init() {
+        registerProtocol("net.pipe", newNamedPipeClient)
+}
+
+// newNamedPipeClient creates a new Client instance bound to a named pipe stream
+// server.
+func newNamedPipeClient(path string) (Client, error) {
+        if path == "" {
+                return nil, errors.New("streamclient: cannot have empty named pipe path")
+        }
+
+        return &clientImpl{func() (io.WriteCloser, error) {
+                return npipe.Dial(fmt.Sprintf(`\\.\pipe\%s`, path))
+        }}, nil
+}