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

tests/kernel/unsorted/mixin_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 Base {
+  baseFoo() {
+    print('Base.baseFoo()');
+    return 1;
+  }
+
+  foo() {
+    print('Base.foo()');
+    return 1;
+  }
+}
+
+class Mixin {
+  mixinFoo() {
+    print('Mixin.mixinFoo()');
+    return 2;
+  }
+
+  foo() {
+    print('Mixin.foo()');
+    return 2;
+  }
+}
+
+class Mixin2 {
+  mixin2Foo() {
+    print('Mixin2.mixin2Foo()');
+    return 3;
+  }
+
+  foo() {
+    print('Mixin2.foo()');
+    return 3;
+  }
+}
+
+class Sub extends Base with Mixin, Mixin2 {
+  subFoo() {
+    print('Sub.subFoo()');
+    return 4;
+  }
+
+  foo() {
+    print('Sub.foo()');
+    return 4;
+  }
+}
+
+main() {
+  var o = new Sub();
+
+  Expect.isTrue(o.baseFoo() == 1);
+  Expect.isTrue(o.mixinFoo() == 2);
+  Expect.isTrue(o.mixin2Foo() == 3);
+  Expect.isTrue(o.subFoo() == 4);
+  Expect.isTrue(o.foo() == 4);
+}
+