Generate code for some switch statements.

dart/frog/tests/leg_only/src/SwitchTest.dart

+// Copyright (c) 2012, 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.
+
+switcher(val) {
+  var x = 0;
+  switch (val) {
+  case 1:
+    x = 100;
+    break;
+  case 2:
+    x = 200;
+    break;
+  case 3:
+    x = 300;
+    break;
+  default:
+    return 400;
+    break; // Intentional dead code (regression test for crash).
+  }
+  return x;
+}
+
+main() {
+  Expect.equals(100, switcher(1));
+  Expect.equals(200, switcher(2));
+  Expect.equals(300, switcher(3));
+  Expect.equals(400, switcher(4));
+}