Hide collection-dev library.

tests/corelib/hidden_library_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.
+// Test that we can't import the internal hidden library "dart:_collection-dev".
 
-class A {
-  a(x) => x + 1;
-}
-
-f(p) => p("A");
+import "dart:_collection_dev";  /// 01: compile-time error
 
 main() {
-  A a = new A();
-  a.a(1);
-  var v = null;
-  try {
-    v = f(a.a);
-  } catch (e) { }
-
-  Expect.equals(null, v);
+  var x = new Map();
 }