Extract SuperMemberData from JavaScriptBackend

pkg/compiler/lib/src/js_emitter/program_builder/program_builder.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.
 
 library dart2js.js_emitter.program_builder;
 
 import '../../closure.dart' show ClosureFieldElement;
 import '../../common.dart';
 import '../../common/names.dart' show Names, Selectors;
 import '../../compiler.dart' show Compiler;
@@ skipping 683 matching lines @@
     if (code == null) return null;
 
     bool canTearOff = false;
     js.Name tearOffName;
     bool isClosureCallMethod = false;
     bool isNotApplyTarget = !element.isFunction || element.isAccessor;
 
     bool canBeReflected = _methodCanBeReflected(element);
     bool canBeApplied = _methodCanBeApplied(element);
 
-    js.Name aliasName = backend.isAliasedSuperMember(element)
+    js.Name aliasName = backend.superMemberData.isAliasedSuperMember(element)
         ? namer.aliasedSuperMemberPropertyName(element)
         : null;
 
     if (isNotApplyTarget) {
       canTearOff = false;
     } else {
       if (element.enclosingClass.isClosure) {
         canTearOff = false;
         isClosureCallMethod = true;
       } else {
@@ skipping 255 matching lines @@
       Constant constant = new Constant(name, holder, constantValue);
       _constants[constantValue] = constant;
     }
   }
 
   Holder _registerStaticStateHolder() {
     return _registry.registerHolder(namer.staticStateHolder,
         isStaticStateHolder: true);
   }
 }