Allow std{in,out,err} to be a socket

runtime/bin/file.h

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef BIN_FILE_H_
 #define BIN_FILE_H_
 
 #if defined(_WIN32)
 typedef signed __int64 int64_t;
 typedef unsigned __int8 uint8_t;
@@ skipping 28 matching lines @@
   enum DartFileOpenMode {
     kDartRead = 0,
     kDartWrite = 1,
     kDartAppend = 2
   };
 
   enum StdioHandleType {
     kTerminal = 0,
     kPipe = 1,
     kFile = 2,
-    kOther = 3
+    kSocket = 3,
+    kOther = -1
   };
 
   enum FileRequest {
     kExistsRequest = 0,
     kCreateRequest = 1,
     kDeleteRequest = 2,
     kOpenRequest = 3,
     kFullPathRequest = 4,
     kDirectoryRequest = 5,
     kCloseRequest = 6,
@@ skipping 85 matching lines @@
   File(const File&);
   void operator=(const File&);
 
   static dart::Mutex mutex_;
   static int service_ports_size_;
   static Dart_Port* service_ports_;
   static int service_ports_index_;
 };
 
 #endif  // BIN_FILE_H_