Move remaining helpers to BackendHelpers

pkg/compiler/lib/src/closure.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.
 
 library closureToClassMapper;
 
 import 'common.dart';
 import 'common/names.dart' show
     Identifiers;
 import 'common/resolution.dart' show
@@ skipping 178 matching lines @@
       : this.methodElement = closure,
         super(name,
               closure.compilationUnit,
               // By assigning a fresh class-id we make sure that the hashcode
               // is unique, but also emit closure classes after all other
               // classes (since the emitter sorts classes by their id).
               compiler.getNextFreeClassId(),
               STATE_DONE) {
     JavaScriptBackend backend = compiler.backend;
     ClassElement superclass = methodElement.isInstanceMember
-        ? backend.boundClosureClass
-        : backend.closureClass;
+        ? backend.helpers.boundClosureClass
+        : backend.helpers.closureClass;
     superclass.ensureResolved(compiler.resolution);
     supertype = superclass.thisType;
     interfaces = const Link<DartType>();
     thisType = rawType = new InterfaceType(this);
     allSupertypesAndSelf =
         superclass.allSupertypesAndSelf.extendClass(thisType);
     callType = methodElement.type;
   }
 
   Iterable<ClosureFieldElement> get closureFields => _closureFields;
@@ skipping 916 matching lines @@
 
   String get name => typeVariable.name;
 
   int get hashCode => typeVariable.hashCode;
 
   bool operator ==(other) {
     if (other is! TypeVariableLocal) return false;
     return typeVariable == other.typeVariable;
   }
 }