Move error checking from scope creation to error reporter

pkg/analyzer/test/generated/resolver_test.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 analyzer.test.generated.resolver_test;
 
 import 'dart:collection';
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
@@ skipping 181 matching lines @@
   }
 }
 
 @reflectiveTest
 class EnclosedScopeTest extends ResolverTestCase {
   void test_define_duplicate() {
     GatheringErrorListener listener = new GatheringErrorListener();
     Scope rootScope =
         new Scope_EnclosedScopeTest_test_define_duplicate(listener);
     EnclosedScope scope = new EnclosedScope(rootScope);
-    VariableElement element1 =
-        ElementFactory.localVariableElement(AstFactory.identifier3("v1"));
-    VariableElement element2 =
-        ElementFactory.localVariableElement(AstFactory.identifier3("v1"));
+    SimpleIdentifier identifier = AstFactory.identifier3("v1");
+    VariableElement element1 = ElementFactory.localVariableElement(identifier);
+    VariableElement element2 = ElementFactory.localVariableElement(identifier);
     scope.define(element1);
     scope.define(element2);
-    listener.assertErrorsWithSeverities([ErrorSeverity.ERROR]);
+    expect(scope.lookup(identifier, null), element1);
   }
 
   void test_define_normal() {
     GatheringErrorListener listener = new GatheringErrorListener();
     Scope rootScope = new Scope_EnclosedScopeTest_test_define_normal(listener);
     EnclosedScope outerScope = new EnclosedScope(rootScope);
     EnclosedScope innerScope = new EnclosedScope(outerScope);
     VariableElement element1 =
         ElementFactory.localVariableElement(AstFactory.identifier3("v1"));
     VariableElement element2 =
@@ skipping 374 matching lines @@
   Element internalLookup(Identifier identifier, String name,
           LibraryElement referencingLibrary) =>
       null;
 }
 
 @reflectiveTest
 class ScopeTest extends ResolverTestCase {
   void test_define_duplicate() {
     GatheringErrorListener errorListener = new GatheringErrorListener();
     ScopeTest_TestScope scope = new ScopeTest_TestScope(errorListener);
-    VariableElement element1 =
-        ElementFactory.localVariableElement(AstFactory.identifier3("v1"));
-    VariableElement element2 =
-        ElementFactory.localVariableElement(AstFactory.identifier3("v1"));
+    SimpleIdentifier identifier = AstFactory.identifier3("v1");
+    VariableElement element1 = ElementFactory.localVariableElement(identifier);
+    VariableElement element2 = ElementFactory.localVariableElement(identifier);
     scope.define(element1);
     scope.define(element2);
-    errorListener.assertErrorsWithSeverities([ErrorSeverity.ERROR]);
+    expect(scope.lookup(identifier, null), element1);
   }
 
   void test_define_normal() {
     GatheringErrorListener errorListener = new GatheringErrorListener();
     ScopeTest_TestScope scope = new ScopeTest_TestScope(errorListener);
     VariableElement element1 =
         ElementFactory.localVariableElement(AstFactory.identifier3("v1"));
     VariableElement element2 =
         ElementFactory.localVariableElement(AstFactory.identifier3("v2"));
     scope.define(element1);
@@ skipping 3016 matching lines @@
  */
 class _StaleElement extends ElementImpl {
   _StaleElement() : super("_StaleElement", -1);
 
   @override
   get kind => throw "_StaleElement's kind shouldn't be accessed";
 
   @override
   accept(_) => throw "_StaleElement shouldn't be visited";
 }