Fix unresolved classes issues in dart:io.

runtime/bin/stdio_patch.dart

Index: runtime/bin/stdio_patch.dart
diff --git a/runtime/bin/stdio_patch.dart b/runtime/bin/stdio_patch.dart
index bcdc671aea511af35ac17df1a4bbad222ffde869..5dd5d87c2a8e4c1111c911a078f41ea4e65cc371 100644
--- a/runtime/bin/stdio_patch.dart
+++ b/runtime/bin/stdio_patch.dart
@@ -3,8 +3,39 @@
 // BSD-style license that can be found in the LICENSE file.
 
 patch class _StdIOUtils {
-  /* patch */ static _getStdioHandle(Socket socket, int num)
-      native "Socket_GetStdioHandle";
-  /* patch */ static _getStdioHandleType(int num)
-      native "File_GetStdioHandleType";
+  static InputStream _getStdioInputStream() {
+    switch (_getStdioHandleType(0)) {
+      case _STDIO_HANDLE_TYPE_TERMINAL:
+      case _STDIO_HANDLE_TYPE_PIPE:
+      case _STDIO_HANDLE_TYPE_SOCKET:
+        Socket s = new _Socket._internalReadOnly();
+        _getStdioHandle(s, 0);
+        s._closed = false;
+        return s.inputStream;
+      case _STDIO_HANDLE_TYPE_FILE:
+        return new _FileInputStream.fromStdio(0);
+      default:
+        throw new FileIOException("Unsupported stdin type");
+    }
+  }
+
+  static OutputStream _getStdioOutputStream(int fd) {
+    assert(fd == 1 || fd == 2);
+    switch (_getStdioHandleType(fd)) {
+      case _STDIO_HANDLE_TYPE_TERMINAL:
+      case _STDIO_HANDLE_TYPE_PIPE:
+      case _STDIO_HANDLE_TYPE_SOCKET:
+        Socket s = new _Socket._internalWriteOnly();
+        _getStdioHandle(s, fd);
+        s._closed = false;
+        return s.outputStream;
+      case _STDIO_HANDLE_TYPE_FILE:
+        return new _FileOutputStream.fromStdio(fd);
+      default:
+        throw new FileIOException("Unsupported stdin type");
+    }
+  }
 }
+
+_getStdioHandle(Socket socket, int num) native "Socket_GetStdioHandle";
+_getStdioHandleType(int num) native "File_GetStdioHandleType";