Move remaining helpers to BackendHelpers

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 {
 
   ClassStubGenerator get _stubGenerator =>
       new ClassStubGenerator(compiler, namer, backend);
@@ skipping 27 matching lines @@
     emitConstructorsForCSP(cls);
     emitFields(cls, builder);
     emitCheckedClassSetters(cls, builder);
     emitClassGettersSettersForCSP(cls, builder);
     emitInstanceMembers(cls, builder);
     emitStubs(cls.callStubs, builder);
     emitStubs(cls.typeVariableReaderStubs, builder);
     emitRuntimeTypeInformation(cls, builder);
     emitNativeInfo(cls, builder);
 
-    if (classElement == backend.closureClass) {
+    if (classElement == backend.helpers.closureClass) {
       // We add a special getter here to allow for tearing off a closure from
       // itself.
       jsAst.Fun function = js('function() { return this; }');
       jsAst.Name name = namer.getterForMember(Names.call);
       builder.addProperty(name, function);
     }
 
     emitClassBuilderWithReflectionData(cls, builder, enclosingBuilder,
         fragment);
   }
@@ skipping 367 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);
     }
   }
 }