Add support for 'Dynamic' type in the VM.

tests/language/src/DynamicTest.dart

+// Copyright (c) 2011, 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.
+//
+// Dart test program testing the use of 'Dynamic' in generic types.
+
+class M1<K, V> implements Map<K, V> {
+}
+
+class M2<K> implements Map<K, Dynamic> {
+}
+
+class M3 implements Map<String, Dynamic> {
+}
+
+typedef Dynamic F1<T>(Dynamic x, T y);
+
+class HasFieldDynamic {
+  HasFieldDynamic() : Dynamic = "Dynamic" { }
+  var Dynamic;  // Field named Dynamic is allowed.
+}
+
+class HasMethodDynamic {
+  Dynamic() => "Dynamic";  // Method named Dynamic is allowed.
+}
+
+main() {
+  M1<Dynamic, Dynamic> m1 = new M1<Dynamic, Dynamic>();
+  Expect.isTrue(m1 is Map<Dynamic, num>);
+  Expect.isTrue(m1 is Map<String, Dynamic>);
+  Expect.isTrue(m1 is Map<String, num>);
+  Expect.isTrue(m1 is Map<num, String>);
+
+  M2<Dynamic> m2 = new M2<Dynamic>();
+  Expect.isTrue(m2 is Map<Dynamic, num>);
+  Expect.isTrue(m2 is Map<String, Dynamic>);
+  Expect.isTrue(m2 is Map<String, num>);
+  Expect.isTrue(m2 is Map<num, String>);
+
+  M3 m3 = new M3();
+  Expect.isTrue(m3 is Map<Dynamic, num>);
+  Expect.isTrue(m3 is Map<String, Dynamic>);
+  Expect.isTrue(m3 is Map<String, num>);
+  Expect.isTrue(m3 is !Map<num, String>);
+
+  F1<int> f1 = (String s, int i) => s[i];
+  Expect.isTrue(f1 is F1<int>);
+
+  HasFieldDynamic has_field = new HasFieldDynamic();
+  Expect.equals("Dynamic", has_field.Dynamic);
+
+  HasMethodDynamic has_method = new HasMethodDynamic();
+  Expect.equals("Dynamic", has_method.Dynamic());
+
+  {
+    int Dynamic = 0;  // Local variable named Dynamic is allowed.
+    Expect.equals(0, Dynamic);
+  }
+}