Add unittest entrypoint for node/frog.

client/testing/unittest/unittest_node.dart

+// 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 simple unit test entrypoint for running tests on node compiled with frog.
+ */
+#library("unittest");
+
+#import('../../../frog/lib/node/node.dart');
+
+#source("shared.dart");
+
+_platformInitialize() {
+  // Do nothing.
+}
+
+_platformDefer(void callback()) {
+  setTimeout(callback, 0);
+}
+
+_platformStartTests() {
+  // Do nothing.
+}
+
+_platformCompleteTests(int testsPassed, int testsFailed, int testsErrors) {
+  // Print each test's result.
+  for (final test in _tests) {
+    print('${test.result.toUpperCase()}: ${test.description}');
+
+    if (test.message != '') {
+      print('  ${test.message}');
+    }
+  }
+
+  // Show the summary.
+  print('');
+
+  if (testsPassed == 0 && testsFailed == 0 && testsErrors == 0) {
+    print('No tests found.');
+  } else if (testsFailed == 0 && testsErrors == 0) {
+    print('All $testsPassed tests passed.');
+  } else {
+    print('$testsPassed PASSED, $testsFailed FAILED, $testsErrors ERRORS');
+  }
+}