Import rasta tests.

pkg/fasta/test/rasta/bad_unicode.dart

Index: pkg/fasta/test/rasta/bad_unicode.dart
diff --git a/pkg/fasta/test/rasta/bad_unicode.dart b/pkg/fasta/test/rasta/bad_unicode.dart
new file mode 100644
index 0000000000000000000000000000000000000000..51c6502f1ee859621bc99a07780fcf7665fddb8e
--- /dev/null
+++ b/pkg/fasta/test/rasta/bad_unicode.dart
@@ -0,0 +1,7 @@
+// Copyright (c) 2016, 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.md file.
+
+main() {
+  print("\u00"); // Bad Unicode escape, must have 4 hex digits.
+}