Revert "Use browsers JSON.parse for parsing JSON (#3)"

runtime/lib/json_patch.dart

Index: runtime/lib/json_patch.dart
diff --git a/runtime/lib/json_patch.dart b/runtime/lib/json_patch.dart
deleted file mode 100644
index 0b637a15f40b9ed514e80097394caf78d5b88517..0000000000000000000000000000000000000000
--- a/runtime/lib/json_patch.dart
+++ /dev/null
@@ -1,9 +0,0 @@
-// Copyright (c) 2013, 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.
-
-// JSON parsing and serialization.
-
-patch parse(String json, [reviver(var key, var value)]) {
-  return _parse(json, reviver);
-}