Remove requiredTypes

pkg/compiler/lib/src/resolution/resolution.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.resolution;
 
 import 'dart:collection' show Queue;
 
 import '../common.dart';
 import '../common/names.dart' show
     Identifiers;
 import '../common/resolution.dart' show
     Parsing,
     Resolution,
     ResolutionImpact;
 import '../common/tasks.dart' show
     CompilerTask,
     DeferredAction;
 import '../compiler.dart' show
     Compiler;
 import '../compile_time_constants.dart' show
     ConstantCompiler;
 import '../constants/values.dart' show
     ConstantValue;
+import '../core_types.dart' show
+    CoreTypes;
 import '../dart_types.dart';
 import '../elements/elements.dart';
 import '../elements/modelx.dart' show
     BaseClassElementX,
     BaseFunctionElementX,
     ConstructorElementX,
     FieldElementX,
     FunctionElementX,
     GetterElementX,
     MetadataAnnotationX,
@@ skipping 28 matching lines @@
   final ConstantCompiler constantCompiler;
 
   ResolverTask(Compiler compiler, this.constantCompiler) : super(compiler);
 
   String get name => 'Resolver';
 
   Resolution get resolution => compiler.resolution;
 
   Parsing get parsing => compiler.parsing;
 
+  CoreTypes get coreTypes => compiler.coreTypes;
+
   ResolutionImpact resolve(Element element) {
     return measure(() {
       if (Elements.isErroneous(element)) {
         // TODO(johnniwinther): Add a predicate for this.
         assert(invariant(element, element is! ErroneousElement,
             message: "Element $element expected to have parse errors."));
         _ensureTreeElements(element);
         return const ResolutionImpact();
       }
 
@@ skipping 274 matching lines @@
       // TODO(johnniwinther): Avoid analyzing initializers if
       // [Compiler.analyzeSignaturesOnly] is set.
       visitor.visit(initializer);
     } else if (modifiers.isConst) {
       reporter.reportErrorMessage(
           element, MessageKind.CONST_WITHOUT_INITIALIZER);
     } else if (modifiers.isFinal && !element.isInstanceMember) {
       reporter.reportErrorMessage(
           element, MessageKind.FINAL_WITHOUT_INITIALIZER);
     } else {
-      registry.registerInstantiatedClass(compiler.nullClass);
+      registry.registerInstantiatedType(coreTypes.nullType);
     }
 
     if (Elements.isStaticOrTopLevelField(element)) {
       visitor.addDeferredAction(element, () {
         if (element.modifiers.isConst) {
           element.constant = constantCompiler.compileConstant(element);
         } else {
           constantCompiler.compileVariable(element);
         }
       });
@@ skipping 697 matching lines @@
   TreeElements get treeElements {
     assert(invariant(this, _treeElements !=null,
         message: "TreeElements have not been computed for $this."));
     return _treeElements;
   }
 
   void reuseElement() {
     _treeElements = null;
   }
 }