Fixed the last unit test that was failing with the new task model

pkg/analyzer/lib/src/task/dart.dart

 // Copyright (c) 2015, 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 analyzer.src.task.dart;
 
 import 'dart:collection';
 
 import 'package:analyzer/src/context/cache.dart';
 import 'package:analyzer/src/generated/ast.dart';
@@ skipping 2660 matching lines @@
       //
       NodeLocator locator = new NodeLocator(variable.nameOffset);
       AstNode node = locator.searchWithin(unit);
       VariableDeclaration declaration = node
           .getAncestor((AstNode ancestor) => ancestor is VariableDeclaration);
       if (declaration == null || declaration.name != node) {
         throw new AnalysisException(
             "NodeLocator failed to find a variable's declaration");
       }
       Expression initializer = declaration.initializer;
-      initializer.accept(new ResolutionEraser());
+      ResolutionEraser.erase(initializer, eraseDeclarations: false);
       ResolutionContext resolutionContext =
           ResolutionContextBuilder.contextFor(initializer, errorListener);
       ResolverVisitor visitor = new ResolverVisitor(
           variable.library, variable.source, typeProvider, errorListener,
           nameScope: resolutionContext.scope);
       if (resolutionContext.enclosingClassDeclaration != null) {
         visitor.prepareToResolveMembersInClass(
             resolutionContext.enclosingClassDeclaration);
       }
       visitor.initForIncrementalResolution();
@@ skipping 1404 matching lines @@
 
   @override
   bool moveNext() {
     if (_newSources.isEmpty) {
       return false;
     }
     currentTarget = _newSources.removeLast();
     return true;
   }
 }