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

tests/kernel/unsorted/superclass_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.
+
+import 'expect.dart';
+
+class A {
+  A() {
+    print("A");
+  }
+
+  hello() {
+    print("A.hello()");
+    return 1;
+  }
+
+  hello1(a) {
+    print("A.hello1()");
+    print(a);
+    return 1;
+  }
+
+  foo(a, [b]) {
+    print("A.foo()");
+    print(a);
+    print(b);
+    return 1;
+  }
+
+  bar(a, {b}) {
+    print("A.bar()");
+    print(a);
+    print(b);
+    return 1;
+  }
+}
+
+class B extends A {
+  hello() {
+    print("B.hello()");
+    return 2;
+  }
+
+  bar(a, {b}) {
+    print("B.bar()");
+    print(a);
+    print(b);
+    return 2;
+  }
+}
+
+main() {
+  var o = new B();
+
+  // Base class methods.
+  Expect.isTrue(o.hello1(1) == 1);
+  Expect.isTrue(o.foo(1) == 1);
+  Expect.isTrue(o.foo(1, 2) == 1);
+
+  // Overwritten methods.
+  Expect.isTrue(o.hello() == 2);
+  Expect.isTrue(o.bar(1) == 2);
+  Expect.isTrue(o.bar(1, b: 2) == 2);
+}