Fix for triple-slash dartdocs

sdk/lib/_internal/dartdoc/test/comment_map_test.dart

Index: sdk/lib/_internal/dartdoc/test/comment_map_test.dart
diff --git a/sdk/lib/_internal/dartdoc/test/comment_map_test.dart b/sdk/lib/_internal/dartdoc/test/comment_map_test.dart
new file mode 100644
index 0000000000000000000000000000000000000000..3d6c4c939df403ca2af615197ed787d445462845
--- /dev/null
+++ b/sdk/lib/_internal/dartdoc/test/comment_map_test.dart
@@ -0,0 +1,38 @@
+// 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.
+
+/// Unit tests for comment map.
+library commentMapTests;
+
+import 'dart:uri';
+import 'dart:mirrors';
+
+import '../../compiler/implementation/scanner/scannerlib.dart' as dart2js;
+
+// TODO(rnystrom): Better path to unittest.
+import '../../../../../pkg/unittest/lib/unittest.dart';
+
+// TODO(rnystrom): Use "package:" URL (#4968).
+part '../lib/src/dartdoc/comment_map.dart';
+
+class FakeSourceLocation implements SourceLocation {
+  Uri get sourceUri => new Uri('file:///tmp/test.dart');
+  int get offset => 69;
+  String get sourceText => """
+    /// Testing
+    ///     var testing = 'this is source code';
+    get foo => 'bar';
+  """;
+}
+
+main() {
+  test('triple slashed comments retain newlines', () {
+    Commentmap cm = new CommentMap();
+    var comment = cm.find(new FakeSourceLocation());
+    expect(
+      comment,
+      equals("Testing\n    var testing = 'this is source code';")
+    );
+  });
+}