Reland "Merge more Kernel infrastructure from kernel_sdk SDK fork."

tests/kernel/unsorted/block_scope_test.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.
+
+// Tests of block scoping.
+
+import 'expect.dart';
+
+bool oracle() => true;
+
+test0() {
+  var x = 'outer', y = x;
+  Expect.isTrue(x == 'outer');
+  Expect.isTrue(y == 'outer');
+  { var x = 'inner';
+    Expect.isTrue(x == 'inner');
+    Expect.isTrue(y == 'outer');
+  }
+  Expect.isTrue(x == 'outer');
+  Expect.isTrue(y == 'outer');
+
+  if (oracle()) {
+    var y = 'inner';
+    Expect.isTrue(x == 'outer');
+    Expect.isTrue(y == 'inner');
+  } else {
+    Expect.isTrue(false);
+  }
+  Expect.isTrue(x == 'outer');
+  Expect.isTrue(y == 'outer');
+}
+
+var x = 'toplevel';
+
+test1() {
+  var y = 'outer';
+  Expect.isTrue(x == 'toplevel');
+  Expect.isTrue(y == 'outer');
+  { var x = 'inner';
+    Expect.isTrue(x == 'inner');
+    Expect.isTrue(y == 'outer');
+  }
+  Expect.isTrue(x == 'toplevel');
+  Expect.isTrue(y == 'outer');
+
+  if (oracle()) {
+    var y = 'inner';
+    Expect.isTrue(x == 'toplevel');
+    Expect.isTrue(y == 'inner');
+  } else {
+    Expect.isTrue(false);
+  }
+  Expect.isTrue(x == 'toplevel');
+  Expect.isTrue(y == 'outer');
+}
+
+main() {
+  test0();
+  test1();
+}