fix PolymerElement.bind to call reflectPropertyToAttribute w/ prop name

pkg/polymer/test/prop_attr_bind_reflection_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.
+
+import 'dart:async' show Completer;
+import 'dart:html';
+import 'package:unittest/unittest.dart';
+import 'package:unittest/html_config.dart';
+import 'package:polymer/polymer.dart';
+
+@CustomTag('my-child-element')
+class MyChildElement extends PolymerElement {
+  @published int camelCase;
+  @published int lowercase;
+
+  MyChildElement.created() : super.created();
+
+  // Make this a no-op, so we can verify the initial
+  // reflectPropertyToAttribute works.
+  observeAttributeProperty(name) { }
+}
+
+@CustomTag('my-element')
+class MyElement extends PolymerElement {
+  @observable int volume = 11;
+
+  MyElement.created() : super.created();
+}
+
+main() {
+  useHtmlConfiguration();
+
+  setUp(() => Polymer.onReady);
+
+  test('attribute reflected to property name', () {
+    var child = query('my-element').shadowRoot.query('my-child-element');
+    expect(child.lowercase, 11);
+    expect(child.camelCase, 11);
+
+    expect('11', child.attributes['lowercase']);
+    expect('11', child.attributes['camelcase']);
+  });
+}