Add attribute information table so we generate correct setters.

lib/src/emitters.dart

Index: lib/src/emitters.dart
diff --git a/lib/src/emitters.dart b/lib/src/emitters.dart
index 97c37e82b5cf7b268789d2b55e8e03fe5c0f6ab3..46d6493ef8151d8d43f126a4d033636a9ad7292b 100644
--- a/lib/src/emitters.dart
+++ b/lib/src/emitters.dart
@@ -18,6 +18,7 @@ import 'codegen.dart' as codegen;
 import 'file_system/path.dart';
 import 'files.dart';
 import 'html5_utils.dart';
+import 'html5_setters.g.dart';
 import 'info.dart';
 import 'messages.dart';
 import 'utils.dart';
@@ -90,10 +91,7 @@ class ElementFieldEmitter extends Emitter<ElementInfo> {
   ElementFieldEmitter(ElementInfo info) : super(info);
 
   void emitDeclarations(Context context) {
-    var type = htmlElementNames[elem.tagName];
-    // Note: this will eventually be the component's class name if it is a
-    // known x-tag.
-    if (type == null) type = 'UnknownElement';
+    var type = typeForHtmlTag(elem.tagName);
     context.declarations.add('autogenerated.$type ${elemInfo.identifier};');
   }
 
@@ -230,23 +228,25 @@ class DataBindingEmitter extends Emitter<ElementInfo> {
           ''');
         }
       } else {
+        // Note: it is important for correctness to use the DOM setter if it
+        // is available. Otherwise changes will not be applied. This is most
+        // easily observed with "InputElement.value", ".checked", etc.
+        var setter = null;
+        var typeName = typeForHtmlTag(elem.tagName);
+        while (typeName != null) {
+          var fields = htmlElementFields[typeName];
+          if (fields != null) setter = fields[name];
+          if (setter != null) break;
+          typeName = htmlElementExtends[typeName];
+        }
+        if (setter == null) setter = 'attributes["$name"]';
+
         var val = attrInfo.boundValue;
         var stopperName = attrInfo.stopperNames[0];
-        var setter;
-        // TODO(sigmund): use setters when they are available (issue #112)
-        //                Need to know if an attr is known for an element.
-        if ((elem.tagName == 'input' &&
-             (name == 'value' || name == 'checked')) ||
-            name == 'hidden') {
-          setter = name;
-        } else {
-          setter = 'attributes["$name"]';
-        }
         context.insertedMethod.add('''
             $stopperName = autogenerated.watchAndInvoke(() => $val, (e) {
             $elemField.$setter = e.newValue;
-            });
-        ''');
+            });''');
       }
     });