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

tests/kernel/unsorted/load_store_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 reading and writing to variables.
+
+import 'expect.dart';
+
+test0() {
+  var x0 = 0, x1;
+  Expect.isTrue(x0 == 0);
+  Expect.isTrue(x1 == null);
+  x0 = 1;
+  Expect.isTrue(x0 == 1);
+  Expect.isTrue((x0 = 2) == 2);
+  Expect.isTrue(x0 == 2);
+}
+
+var x2 = 0, x3;
+
+test1() {
+  Expect.isTrue(x2 == 0);
+  Expect.isTrue(x3 == null);
+  x2 = 1;
+  Expect.isTrue(x2 == 1);
+  Expect.isTrue((x2 = 2) == 2);
+  Expect.isTrue(x2 == 2);
+}
+
+class C {
+  static var x4 = 0;
+  static var x5;
+}
+
+test3() {
+  Expect.isTrue(C.x4 == 0);
+  Expect.isTrue(C.x5 == null);
+  C.x4 = 1;
+  Expect.isTrue(C.x4 == 1);
+  Expect.isTrue((C.x4 = 2) == 2);
+  Expect.isTrue(C.x4 == 2);
+}
+
+class D {
+  var x6 = 0;
+  var x7;
+}
+
+test4() {
+  var d = new D();
+  Expect.isTrue(d.x6 == 0);
+  Expect.isTrue(d.x7 == null);
+  d.x6 = 1;
+  Expect.isTrue(d.x6 == 1);
+  Expect.isTrue((d.x6 = 2) == 2);
+  Expect.isTrue(d.x6 == 2);
+}
+
+main() {
+  test0();
+  test1();
+  test3();
+  test4();
+}