Remove BackendClasses and JavaScriptBackendClasses.

pkg/compiler/lib/src/constant_system_dart.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 dart2js.constant_system.dart;
 
-import 'common/backend_api.dart' show BackendClasses;
 import 'constants/constant_system.dart';
 import 'constants/values.dart';
 import 'common_elements.dart' show CommonElements;
 import 'elements/types.dart';
 import 'elements/resolution_types.dart' show DartTypes;
 import 'tree/dartstring.dart' show DartString;
 
 const DART_CONSTANT_SYSTEM = const DartConstantSystem();
 
 class BitNotOperation implements UnaryOperation {
@@ skipping 424 matching lines @@
 
   @override
   NullConstantValue createNull() => new NullConstantValue();
 
   @override
   ListConstantValue createList(InterfaceType type, List<ConstantValue> values) {
     return new ListConstantValue(type, values);
   }
 
   @override
-  MapConstantValue createMap(
-      CommonElements commonElements,
-      BackendClasses backendClasses,
-      InterfaceType type,
-      List<ConstantValue> keys,
-      List<ConstantValue> values) {
+  MapConstantValue createMap(CommonElements commonElements, InterfaceType type,
+      List<ConstantValue> keys, List<ConstantValue> values) {
     return new MapConstantValue(type, keys, values);
   }
 
   @override
-  ConstantValue createType(CommonElements commonElements,
-      BackendClasses backendClasses, DartType type) {
-    // TODO(johnniwinther): Change the `Type` type to
-    // `compiler.commonElements.typeType` and check the backend specific value
-    // in [checkConstMapKeysDontOverrideEquals] in 'members.dart'.
-    InterfaceType implementationType = backendClasses.typeType;
+  ConstantValue createType(CommonElements commonElements, DartType type) {
+    InterfaceType implementationType = commonElements.typeLiteralType;
     return new TypeConstantValue(type, implementationType);
   }
 
   @override
-  ConstantValue createSymbol(CommonElements commonElements,
-      BackendClasses backendClasses, String text) {
+  ConstantValue createSymbol(CommonElements commonElements, String text) {
     throw new UnsupportedError('DartConstantSystem.createSymbol');
   }
 
   bool isInt(ConstantValue constant) => constant.isInt;
   bool isDouble(ConstantValue constant) => constant.isDouble;
   bool isString(ConstantValue constant) => constant.isString;
   bool isBool(ConstantValue constant) => constant.isBool;
   bool isNull(ConstantValue constant) => constant.isNull;
 
   bool isSubtype(DartTypes types, DartType s, DartType t) {
     return types.isSubtype(s, t);
   }
 }