Add Stdio.readByteSync and Stdio.readLineSync.

tests/standalone/io/stdin_sync_test.dart

+// Copyright (c) 2013, 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.
+
+import "dart:io";
+import "dart:json";
+
+void test(String line, List<String> expected) {
+  var script = new Path(Platform.script).directoryPath;
+  script = script.append("stdin_sync_script.dart");
+  Process.start(Platform.executable,
+                [script.toNativePath()]..addAll(
+                    expected.map(stringify))).then((process) {
+    process.stdin.write(line);
+    process.stdin.close();
+    process.stderr
+        .transform(new StringDecoder())
+        .transform(new LineTransformer())
+        .fold(new StringBuffer(), (b, d) => b..write(d))
+        .then((data) {
+          if (data.toString() != '') throw "Bad output: '$data'";
+        });
+    process.stdout
+        .transform(new StringDecoder())
+        .transform(new LineTransformer())
+        .fold(new StringBuffer(), (b, d) => b..write(d))
+        .then((data) {
+          if (data.toString() != 'true') throw "Bad output: '$data'";
+        });
+  });
+}
+
+void main() {
+  test("hej\x01\x00\x0d\x0a\x0a4\x0a", ['hej\x01\x00', '', '4']);
+
+  test("hej\u0187", ['hej\u0187']);
+
+  test("hej\rhej\nhej\r", ['hej\rhej', 'hej\r']);
+
+  test("hej\r\r\nhej\r\nhej\r", ['hej\r', 'hej', 'hej\r']);
+
+  test("hej", ['hej']);
+}