Serialize JumpTarget and LabelDefinition.

tests/compiler/dart2js/serialization_test_data.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.
 
 library dart2js.serialization_test_data;
 
 const List<Test> TESTS = const <Test>[
   const Test(const {
     'main.dart': 'main() {}'
   }),
@@ skipping 170 matching lines @@
 }
 main() {
   // Invocation of `MyRandom.nextInt` is only detected knowing the actual 
   // implementation class for `List` and the world impact of its `shuffle` 
   // method.  
   [].shuffle(new MyRandom());
 }'''
   },
   expectedWarningCount: 1,
   expectedInfoCount: 0),
+
+  const Test(const {
+    'main.dart': '''
+main() {
+  loop: for (var a in []) {
+    for (var b in []) {
+      continue loop;
+    }
+    break;
+  }      
+}'''
+  }),
+
 ];
 
 class Test {
   final Map sourceFiles;
   final int expectedErrorCount;
   final int expectedWarningCount;
   final int expectedHintCount;
   final int expectedInfoCount;
 
   const Test(this.sourceFiles, {
     this.expectedErrorCount: 0,
     this.expectedWarningCount: 0,
     this.expectedHintCount: 0,
     this.expectedInfoCount: 0});
 }