Revert two Kernel changes that were causing test failures.

tests/language_2/async_control_structures_test.dart

-// Copyright (c) 2014, 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.
-
-// VMOptions=--optimization-counter-threshold=10 --no-background-compilation
-
-import 'package:expect/expect.dart';
-
-import 'dart:async';
-
-expectThenValue(future, value) {
-  Expect.isTrue(future is Future);
-  future.then((result) {
-    Expect.equals(value, result);
-  });
-}
-
-asyncIf(condition) async {
-  if (condition) {
-    return 1;
-  } else {
-    return 2;
-  }
-  // This return is never reached as the finally block returns from the
-  // function.
-  return 3;
-}
-
-asyncFor(condition) async {
-  for (int i = 0; i < 10; i++) {
-    if (i == 5 && condition) {
-      return 1;
-    }
-  }
-  return 2;
-}
-
-asyncTryCatchFinally(overrideInFinally, doThrow) async {
-  try {
-    if (doThrow) throw 444;
-    return 1;
-  } catch (e) {
-    return e;
-  } finally {
-    if (overrideInFinally) return 3;
-  }
-}
-
-asyncTryCatchLoop() async {
-  var i = 0;
-  var throws = 13;
-  while (true) {
-    try {
-      throw throws;
-    } catch (e) {
-      if (i == throws) {
-        return e;
-      }
-    } finally {
-      i++;
-    }
-  }
-}
-
-asyncImplicitReturn() async {
-  try {} catch (e) {} finally {}
-}
-
-main() {
-  var asyncReturn;
-
-  for (int i = 0; i < 10; i++) {
-    asyncReturn = asyncIf(true);
-    expectThenValue(asyncReturn, 1);
-    asyncReturn = asyncIf(false);
-    expectThenValue(asyncReturn, 2);
-
-    asyncReturn = asyncFor(true);
-    expectThenValue(asyncReturn, 1);
-    asyncReturn = asyncFor(false);
-    expectThenValue(asyncReturn, 2);
-
-    asyncReturn = asyncTryCatchFinally(true, false);
-    expectThenValue(asyncReturn, 3);
-    asyncReturn = asyncTryCatchFinally(false, false);
-    expectThenValue(asyncReturn, 1);
-    asyncReturn = asyncTryCatchFinally(true, true);
-    expectThenValue(asyncReturn, 3);
-    asyncReturn = asyncTryCatchFinally(false, true);
-    expectThenValue(asyncReturn, 444);
-    asyncReturn = asyncTryCatchLoop();
-    expectThenValue(asyncReturn, 13);
-
-    asyncReturn = asyncImplicitReturn();
-    expectThenValue(asyncReturn, null);
-  }
-}