dart2js: emit callstubs in new emitter and rename to stubs.

pkg/compiler/lib/src/js_emitter/native_emitter.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.js_emitter;
 
 class NativeEmitter {
 
   final Map<Element, ClassBuilder> cachedBuilders;
 
@@ skipping 250 matching lines @@
   bool isTrivialClass(Class cls) {
     bool needsAccessor(Field field) {
       return field.needsGetter ||
           field.needsUncheckedSetter ||
           field.needsCheckedSetter;
     }
 
     return
         cls.methods.isEmpty &&
         cls.isChecks.isEmpty &&
-        cls.callStubs.isEmpty &&
+        cls.stubs.isEmpty &&
         !cls.superclass.isMixinApplication &&
         !cls.fields.any(needsAccessor);
   }
 
   void potentiallyConvertDartClosuresToJs(
       List<jsAst.Statement> statements,
       FunctionElement member,
       List<jsAst.Parameter> stubParameters) {
     FunctionSignature parameters = member.functionSignature;
     Element converter = backend.findHelper('convertDartClosureToJS');
@@ skipping 189 matching lines @@
           }
     ''', {'info': infoAccess,
           'constructor': constructorAccess,
           'subclassRead': subclassRead,
           'interceptorsByTagAccess': interceptorsByTagAccess,
           'leafTagsAccess': leafTagsAccess,
           'nativeSuperclassTagName': embeddedNames.NATIVE_SUPERCLASS_TAG_NAME,
           'allowNativesSubclassing': true});
   }
 }