Create Namer and Emitter on codegen start.

pkg/compiler/lib/src/js_emitter/full_emitter/class_emitter.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.
 
 part of dart2js.js_emitter.full_emitter;
 
 class ClassEmitter extends CodeEmitterHelper {
+  final ClosedWorld closedWorld;
+
+  ClassEmitter(this.closedWorld);
+
   ClassStubGenerator get _stubGenerator =>
-      new ClassStubGenerator(compiler, namer, backend);
+      new ClassStubGenerator(namer, backend, codegenWorld, closedWorld,
+          enableMinification: compiler.options.enableMinification);
 
   /**
    * Documentation wanted -- johnniwinther
    */
   void emitClass(Class cls, ClassBuilder enclosingBuilder, Fragment fragment) {
     ClassElement classElement = cls.element;
 
     assert(invariant(classElement, classElement.isDeclaration));
 
     emitter.needsClassSupport = true;
@@ skipping 397 matching lines @@
         : new Selector.setter(
             new Name(member.name, member.library, isSetter: true));
     String reflectionName = emitter.getReflectionName(selector, name);
     if (reflectionName != null) {
       var reflectable =
           js(backend.isAccessibleByReflection(member) ? '1' : '0');
       builder.addPropertyByName('+$reflectionName', reflectable);
     }
   }
 }