Migrated test block 12 to Dart 2.0.

tests/corelib_2/json_map_test.dart

Index: tests/corelib_2/json_map_test.dart
diff --git a/tests/corelib_strong/json_map_test.dart b/tests/corelib_2/json_map_test.dart
similarity index 96%
rename from tests/corelib_strong/json_map_test.dart
rename to tests/corelib_2/json_map_test.dart
index e4d46eecbed67e7c04de73ea1bdbeb6794e1d3d1..bb47d2d3a11d936d6f5df0cf9a006450aa6f7c06 100644
--- a/tests/corelib_strong/json_map_test.dart
+++ b/tests/corelib_2/json_map_test.dart
@@ -53,7 +53,6 @@ void test(bool revive) {
   testToString();
   testConcurrentModifications();
   testType();
-  testNonStringKeys();
   testClear();
 
   testListEntry();
@@ -307,16 +306,9 @@ void testType() {
   Expect.isTrue(jsonify({}) is HashMap<String, dynamic>);
   Expect.isTrue(jsonify({}) is LinkedHashMap<String, dynamic>);
 
-  Expect.isTrue(jsonify({}) is Map<int, dynamic>);
-  Expect.isTrue(jsonify({}) is HashMap<int, dynamic>);
-  Expect.isTrue(jsonify({}) is LinkedHashMap<int, dynamic>);
-}
-
-void testNonStringKeys() {
-  Map map = jsonify({});
-  map[1] = 2;
-  Expect.equals(1, map.length);
-  Expect.equals(2, map[1]);
+  Expect.isFalse(jsonify({}) is Map<int, dynamic>);
+  Expect.isFalse(jsonify({}) is HashMap<int, dynamic>);
+  Expect.isFalse(jsonify({}) is LinkedHashMap<int, dynamic>);
 }
 
 void testClear() {