Add the dummy test file for the dartdoc tests.

utils/dartdoc/test/dummy.dart

Index: utils/dartdoc/test/dummy.dart
diff --git a/utils/dartdoc/test/dummy.dart b/utils/dartdoc/test/dummy.dart
new file mode 100644
index 0000000000000000000000000000000000000000..8bd6b48d6e25dc0d5958b0ae6d68607cc6686882
--- /dev/null
+++ b/utils/dartdoc/test/dummy.dart
@@ -0,0 +1,16 @@
+// Copyright (c) 2011, 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.
+
+// A dummy library for testing dartdoc name references.
+#library('dummy');
+
+topLevelMethod() => null;
+
+class Class {
+  method(param) => null;
+  get getterOnly() => null;
+  get getterAndSetter() => null;
+  set getterAndSetter(val) => null;
+  set setterOnly(val) => null;
+}