Get the most basic mixin applications working.

tests/language/mixin_method_test.dart

+// Copyright (c) 2013, 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.
+
+class S {
+  foo() => "S-foo";
+  baz() => "S-baz";
+}
+
+class M1 {
+  bar() => "M1-bar";
+}
+
+class M2 {
+  bar() => "M2-bar";
+  baz() => "M2-baz";
+  fez() => "M2-fez";
+}
+
+typedef C = S with M1;
+typedef D = S with M1, M2;
+typedef E = S with M2, M1;
+
+class F extends E {
+  fez() => "F-fez";
+}
+
+main() {
+  var c = new C();
+  Expect.equals("S-foo", c.foo());
+  Expect.equals("M1-bar", c.bar());
+  Expect.equals("S-baz", c.baz());
+  Expect.throws(() => c.fez(), (error) => error is NoSuchMethodError);
+
+  var d = new D();
+  Expect.equals("S-foo", d.foo());
+  Expect.equals("M2-bar", d.bar());
+  Expect.equals("M2-baz", d.baz());
+  Expect.equals("M2-fez", d.fez());
+
+  var e = new E();
+  Expect.equals("S-foo", e.foo());
+  Expect.equals("M1-bar", e.bar());
+  Expect.equals("M2-baz", e.baz());
+  Expect.equals("M2-fez", e.fez());
+
+  var f = new F();
+  Expect.equals("S-foo", f.foo());
+  Expect.equals("M1-bar", f.bar());
+  Expect.equals("M2-baz", f.baz());
+  Expect.equals("F-fez", f.fez());
+}