fix #136, support watch exprs and two way bindings for component fields

test/emitter_test.dart

Index: test/emitter_test.dart
diff --git a/test/emitter_test.dart b/test/emitter_test.dart
index 3d1c530129938918ccfac2e8574f7c42420e0555..9617406da3e7ebaf33be188a6f5c8bf2d6bd56eb 100644
--- a/test/emitter_test.dart
+++ b/test/emitter_test.dart
@@ -176,8 +176,7 @@ main() {
     test('created', () {
       var elem = parseSubtree('<div>{{bar}}</div>');
       var emitter = new ContentFieldEmitter(analyzeElement(elem).children[0]);
-      expect(_created(emitter),
-        '__binding0 = autogenerated.nodeForBinding(bar);');
+      expect(_created(emitter), "__binding0 = new autogenerated.Text('');");
     });
 
     test('inserted', () {
@@ -260,7 +259,7 @@ main() {
       var emitter = new AttributeEmitter(analyzeElement(elem));
       expect(_inserted(emitter), equalsIgnoringWhitespace(
           '__stoppers1.add(autogenerated.watchAndInvoke(() => '
-          'bar, (__e) { __e0.attributes["foo"] = __e.newValue; }));'));
+          "bar, (__e) { __e0.attributes['foo'] = __e.newValue; }));"));
     });
 
     test('inserted for 1-way binding with dom accessor', () {
@@ -284,7 +283,7 @@ main() {
       var emitter = new AttributeEmitter(analyzeElement(elem));
       expect(_inserted(emitter), equalsIgnoringWhitespace(
           '__stoppers1.add(autogenerated.watchAndInvoke(() => bar, (__e) { '
-          '__e0.attributes["data-foo"] = __e.newValue; }));'));
+          "__e0.attributes['data-foo'] = __e.newValue; }));"));
     });
 
     test('inserted for class', () {