Add dart:web to dart2js and editor, containing only htmlEscape.

lib/web/web.dart

Index: lib/web/web.dart
diff --git a/lib/web/web.dart b/lib/web/web.dart
new file mode 100644
index 0000000000000000000000000000000000000000..47bbd05f8b11f7b11bf39061f949a3ab36bb2eee
--- /dev/null
+++ b/lib/web/web.dart
@@ -0,0 +1,14 @@
+// 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.
+
+#library("web");

[kasperl, 2012/06/18 07:10:24]

You should make sure to add documentation to these methods (and also the
library) so that it looks nice on api.dartlang.org. You should also update
utils/apidoc/apidoc.dart.

+
+String htmlEscape(String text) {
+  // TODO(efortuna): A more efficient implementation.
+  return text.replaceAll("&", "&")
+             .replaceAll("<", "&lt;")
+             .replaceAll(">", "&gt;")
+             .replaceAll('"', "&quot;")
+             .replaceAll("'", "&apos;");
+}