dart2js: store fields in the model and make the emitters use it.

pkg/compiler/lib/src/js_emitter/old_emitter/emitter.dart

 // Copyright (c) 2014, 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;
 
 
 class OldEmitter implements Emitter {
   final Compiler compiler;
   final CodeEmitterTask task;
@@ skipping 1361 matching lines @@
   void emitLibrary(Library library) {
     LibraryElement libraryElement = library.element;
 
     emitStaticFunctions(library.statics);
 
     ClassBuilder libraryBuilder = getElementDescriptor(libraryElement);
     for (Class cls in library.classes) {
       emitClass(cls, libraryBuilder);
     }
 
-    classEmitter.emitFields(libraryElement, libraryBuilder, emitStatics: true);
+    classEmitter.emitFields(library, libraryBuilder, emitStatics: true);
   }
 
   void emitMainOutputUnit(Program program,
                           Map<OutputUnit, String> deferredLoadHashes,
                           CodeBuffer nativeBuffer) {
     Fragment mainFragment = program.fragments.first;
     OutputUnit mainOutputUnit = mainFragment.outputUnit;
 
     LineColumnCollector lineColumnCollector;
     List<CodeOutputListener> codeOutputListeners;
@@ skipping 707 matching lines @@
     for (Element element in compiler.enqueuer.codegen.newlyEnqueuedElements) {
       if (element.isInstanceMember) {
         cachedClassBuilders.remove(element.enclosingClass);
 
         nativeEmitter.cachedBuilders.remove(element.enclosingClass);
 
       }
     }
   }
 }