Support break in switch and break/continue in do statements

tests/compiler/dart2js/kernel/compile_from_dill_test_helper.dart

 // Copyright (c) 2017, 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.
 
 // Helper to test compilation equivalence between source and .dill based
 // compilation.
 library dart2js.kernel.compile_from_dill_test_helper;
 
 import 'dart:async';
 import 'dart:io';
@@ skipping 60 matching lines @@
   var w = x == null ? null : x.toString();
   for (int i = 0; i < 10; i++) {
     if (i == 5) continue;
     x = i;
     if (i == 5) break;
   }
   int i = 0;
   while (i < 10) {
     if (i == 5) continue;
     x = i;
-    if (i == 5) break;
+    if (i == 7) break;
+    i++;
   }
   for (var v in [3, 5]) {
     if (v == 5) continue;
     x = v;
-    if (v == 5) break;
+    if (v == 7) break;
+  }
+  do {
+    // TODO(johnniwinther): Support js ast equivalence to handle label name
+    // mismatches. Enable the continue test:
+    //if (i == 5) continue;
+    x = i;
+    if (i == 7) break;
+    i++;
+  } while (i < 10);
+  switch (x) {
+  case 0:
+    x = 7;
+    break;
+  case 1:
+    x = 9;
+    break;
+  default:
+    x = 11;
+    break;
   }
   x = toplevel;
   print(x);
   return x;
 }
 '''
 };
 
 enum ResultKind { crashes, errors, warnings, success, failure }
 
@@ skipping 112 matching lines @@
     }
     Map<String, BufferedOutputSink> map2 = collector2.outputMap[outputType];
     checkSets(map1.keys, map2.keys, 'output', equality);
     map1.forEach((String name, BufferedOutputSink output1) {
       BufferedOutputSink output2 = map2[name];
       Expect.stringEquals(output1.text, output2.text);
     });
   });
   return ResultKind.success;
 }