Add corelib tests

test/codegen/corelib/queue_first_test.dart

+// 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.
+
+library queue.first.test;
+
+import "package:expect/expect.dart";
+import 'dart:collection' show Queue;
+
+main() {
+  Queue<int> queue1 = new Queue<int>();
+  queue1..add(11)
+      ..add(12)
+      ..add(13);
+  Queue queue2 = new Queue();
+
+  Expect.equals(11, queue1.first);
+  Expect.throws(() => queue2.first, (e) => e is StateError);
+}