Add a type kind to TypedSelector. A typed selector can either be

sdk/lib/_internal/compiler/implementation/enqueue.dart

 // Copyright (c) 2012, 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.
 
 part of dart2js;
 
 class EnqueueTask extends CompilerTask {
   final ResolutionEnqueuer resolution;
   final CodegenEnqueuer codegen;
 
@@ skipping 336 matching lines @@
 
   void registerDynamicSetter(SourceString methodName, Selector selector) {
     registerInvokedSetter(methodName, selector);
   }
 
   void registerFieldGetter(SourceString getterName,
                            LibraryElement library,
                            DartType type) {
     task.measure(() {
       Selector getter = new Selector.getter(getterName, library);
-      registerNewSelector(getterName,
-                          new TypedSelector(type, getter),
-                          universe.fieldGetters);
+      registerNewSelector(
+          getterName,
+          new TypedSelector.subclass(type, getter),

[kasperl, 2013/02/11 13:11:50]

Aren't we throwing away information at this point? Couldn't this take a selector
instead of a getterName, a library, and a type? The same goes for the setter.

[ngeoffray, 2013/02/11 14:20:29]

Actually, we should just take an element. Done.

+          universe.fieldGetters);
     });
   }
 
   void registerFieldSetter(SourceString setterName,
                            LibraryElement library,
                            DartType type) {
     task.measure(() {
       Selector setter = new Selector.setter(setterName, library);
-      registerNewSelector(setterName,
-                          new TypedSelector(type, setter),
-                          universe.fieldSetters);
+      registerNewSelector(
+          setterName,
+          new TypedSelector.subclass(type, setter),
+          universe.fieldSetters);
     });
   }
 
   void registerIsCheck(DartType type) {
     universe.isChecks.add(type);
   }
 
   void forEach(f(WorkItem work));
 
   void logSummary(log(message)) {
@@ skipping 162 matching lines @@
     while(!queue.isEmpty) {
       // TODO(johnniwinther): Find an optimal process order for codegen.
       f(queue.removeLast());
     }
   }
 
   void _logSpecificSummary(log(message)) {
     log('Compiled ${generatedCode.length} methods.');
   }
 }