Update TodoMVC based on https://github.com/polymer/todomvc

pkg/polymer/lib/src/build/linter.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.
 
 /**
  * Logic to validate that developers are correctly using Polymer constructs.
  * This is mainly used to produce warnings for feedback in the editor.
  */
 library polymer.src.build.linter;
 
@@ skipping 236 matching lines @@
          break;
     }
   }
 
   void run(Document doc) {
     visit(doc);
 
     if (_isEntrypoint && !_dartTagSeen) {
       _logger.error(USE_INIT_DART, span: doc.body.sourceSpan);
     }
-
-    if (_isEntrypoint && !_dartJSSeen) {
-      // TODO(sigmund): remove this when webkitStartDart is gone.
-      _logger.error(USE_DART_JS, span: doc.body.sourceSpan);
-    }
   }
 
   /** Produce warnings for invalid link-rel tags. */
   void _validateLinkElement(Element node) {
     var rel = node.attributes['rel'];
     if (rel != 'import' && rel != 'stylesheet') return;
 
     if (rel == 'import' && _dartTagSeen) {
       _logger.warning(
           "Move HTML imports above your Dart script tag.",
@@ skipping 217 matching lines @@
           span: node.attributeSpans[name]);
       return;
     }
 
     if (!_inPolymerElement) {
       _logger.warning('Inline event handlers are only supported inside '
           'declarations of <polymer-element>.',
           span: node.attributeSpans[name]);
     }
 
-    var eventName = name.substring('on-'.length);
-    if (eventName.contains('-')) {
-      var newEvent = toCamelCase(eventName);
-      _logger.warning('Invalid event name "$name". After the "on-" the event '
-          'name should not use dashes. For example use "on-$newEvent" or '
-          '"on-${newEvent.toLowerCase()}" (both forms are equivalent in HTML).',
-          span: node.attributeSpans[name]);
-    }
-
     if (value.contains('.') || value.contains('(')) {
       _logger.warning('Invalid event handler body "$value". Declare a method '
           'in your custom element "void handlerName(event, detail, target)" '
           'and use the form $name="handlerName".',
           span: node.attributeSpans[name]);
     }
   }
 }
 
 
@@ skipping 17 matching lines @@
 bool _isCustomTag(String name) {
   if (name == null || !name.contains('-')) return false;
   return !_invalidTagNames.containsKey(name);
 }
 
 const String _RED_COLOR = '\u001b[31m';
 const String _MAGENTA_COLOR = '\u001b[35m';
 const String _NO_COLOR = '\u001b[0m';
 
 const String USE_INIT_DART =
-    'To run a polymer applications, you need to call "initPolymer". You can '
+    'To run a polymer application, you need to call "initPolymer". You can '
     'either include a generic script tag that does this for you:'
     '\'<script type="application/dart">export "package:polymer/init.dart";'
     '</script>\' or add your own script tag and call that function. '
     'Make sure the script tag is placed after all HTML imports.';
 
-const String USE_DART_JS =
-    'To run a polymer applications in Dartium, make sure to include'
-    '\'<script src="packages/browser/dart.js"></script>\' in your page';
-
 const String BOOT_JS_DEPRECATED =
     '"boot.js" is now deprecated. Instead, you can initialize your polymer '
     'application by calling "initPolymer()" in your main. If you don\'t have a '
     'main, then you can include our generic main by adding the following '
     'script tag to your page: \'<script type="application/dart">export '
     '"package:polymer/init.dart";</script>\'. Additionally you need to '
     'include: \'<script src="packages/browser/dart.js"></script>\' in the page '
     'too. Make sure these script tags come after all HTML imports.';