Revert "Removes dartc reliance on its own libraries, now can be targeted at any implementation's li…

compiler/lib/implementation/bool.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.
+
+// Adds Dart-methods to the prototype of the JS Boolean function.
+// TODO(floitsch): the following comment needs to be updated once we compile
+// boolean checks with '=== true'.
+// WARNING: 'this' inside this class is always treated as 'true'.
+// That is if (this) ... will always pick the 'then' branch.
+// The reason is that, once compiled to JS, 'this' is represented by a
+// JS Boolean object. However "if (new Boolean(false)) .." picks the then
+// branch.
+class BoolImplementation implements bool native "Boolean" {
+  bool operator ==(other) native;
+
+  // TODO(floitsch): we should intercept toString for primitives, to avoid
+  // creating a wrapper object.
+  String toString() native;
+
+  BoolImplementation toBool() native;
+
+  get dynamic() { return toBool(); }
+}