test rename overhaul: step 8 - language tests

tests/language/src/FieldOverrideTest.dart

-// Copyright (c) 2012, 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.
-// Test overriding of fields.
-
-
-class A {}
-class B1 extends A {}
-class B2 extends A {}
-
-class Super {
-  Super() : super();
-
-  B1 field;
-}
-
-class Sub extends Super {
-  Sub() : super();
-
-  A field;
-}
-
-class SubSub extends Super {
-  SubSub() : super();
-
-  // B2 not assignable to B1
-  B2 field;  /// 01: static type warning
-}
-
-main() {
-  SubSub val1 = new SubSub();
-  val1.field = new B2(); /// 02: static type warning
-  Expect.equals(true, val1.field is B2); /// 02: continued
-
-  Sub val2 = new Sub();
-  val2.field = new A();
-  Expect.equals(true, val2.field is A);
-  Expect.equals(false, val2.field is B1);
-  Expect.equals(false, val2.field is B2);
-
-  Super val3 = new Super();
-  val3.field = new B1();
-  Expect.equals(true, val3.field is B1);
-  Expect.equals(false, val3.field is B2);
-}