Rename mdv -> template_binding, remove experiemntal apis from dart:html

pkg/polymer_expressions/lib/eval.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.
 
 library polymer_expressions.eval;
 
 import 'dart:async';
 import 'dart:collection';
 
 @MirrorsUsed(metaTargets: const [Reflectable, ObservableProperty],
@@ skipping 402 matching lines @@
       : super(value);
 
   accept(Visitor v) => v.visitMapLiteralEntry(this);
 }
 
 class IdentifierObserver extends ExpressionObserver<Identifier>
     implements Identifier {
 
   IdentifierObserver(Identifier value) : super(value);
 
-  String get value => (_expr as Identifier).value;
+  String get value => _expr.value;
 
   _updateSelf(Scope scope) {
     _value = scope[value];
 
     var owner = scope.ownerOf(value);
     if (owner is Observable) {
       var symbol = new Symbol(value);
       _subscription = (owner as Observable).changes.listen((changes) {
         if (changes.any(
             (c) => c is PropertyChangeRecord && c.name == symbol)) {
@@ skipping 211 matching lines @@
    * This does not work for calls that need to pass more than one argument.
    */
   call(arg0) => mirror.invoke(symbol, [arg0], null).reflectee;
 }
 
 class EvalException implements Exception {
   final String message;
   EvalException(this.message);
   String toString() => "EvalException: $message";
 }