Add location information to the JSON reporter.

lib/src/runner/plugin/platform_helpers.dart

 // 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 file.
 
 import 'dart:async';
 
 import 'package:stack_trace/stack_trace.dart';
 import 'package:stream_channel/stream_channel.dart';
 
 import '../../backend/group.dart';
@@ skipping 101 matching lines @@
 
   /// Deserializes [group] into a concrete [Group].
   Group deserializeGroup(Map group) {
     var metadata = new Metadata.deserialize(group['metadata']);
     return new Group(group['name'], (group['entries'] as List).map((entry) {
       var map = entry as Map;
       if (map['type'] == 'group') return deserializeGroup(map);
       return _deserializeTest(map);
     }),
         metadata: metadata,
+        trace: group['trace'] == null ? null : new Trace.parse(group['trace']),
         setUpAll: _deserializeTest(group['setUpAll']),
         tearDownAll: _deserializeTest(group['tearDownAll']));
   }
 
   /// Deserializes [test] into a concrete [Test] class.
   ///
   /// Returns `null` if [test] is `null`.
   Test _deserializeTest(Map test) {
     if (test == null) return null;
 
     var metadata = new Metadata.deserialize(test['metadata']);
+    var trace = test['trace'] == null ? null : new Trace.parse(test['trace']);
     var testChannel = _channel.virtualChannel(test['channel']);
-    return new RunnerTest(test['name'], metadata, testChannel, _mapTrace);
+    return new RunnerTest(
+        test['name'], metadata, trace, testChannel, _mapTrace);
   }
 }