introduce web_components pkg for consolidated polyfills

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 396 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]);
     }
 
-    if (value.contains('.') || value.contains('(')) {

[Jennifer Messerly, 2014/02/08 01:13:29]

this was issuing a bogus warning for things like:

{{@item.tapAction}}

there's actually a test that uses it.

+    if (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]);
     }
   }
 }
 
 
 // These names have meaning in SVG or MathML, so they aren't allowed as custom
@@ skipping 26 matching lines @@
     'Make sure the script tag is placed after all HTML imports.';
 
 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.';