Prepare for decoupling analyzer ASTs from element model.

pkg/analysis_server/lib/src/services/completion/dart/local_reference_contributor.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 services.completion.contributor.dart.local_ref;
 
 import 'dart:async';
 
 import 'package:analysis_server/plugin/protocol/protocol.dart' as protocol
     show Element, ElementKind;
 import 'package:analysis_server/src/provisional/completion/dart/completion_dart.dart';
 import 'package:analysis_server/src/services/completion/dart/completion_manager.dart'
     show DartCompletionRequestImpl;
 import 'package:analysis_server/src/services/completion/dart/local_declaration_visitor.dart'
     show LocalDeclarationVisitor;
 import 'package:analysis_server/src/services/completion/dart/optype.dart';
 import 'package:analysis_server/src/services/correction/strings.dart';
 import 'package:analysis_server/src/utilities/documentation.dart';
 import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/dart/ast/standard_resolution_map.dart';
 import 'package:analyzer/dart/ast/standard_ast_factory.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/src/dart/ast/token.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/generated/utilities_dart.dart' show ParameterKind;
 
 import '../../../protocol_server.dart'
     show CompletionSuggestion, CompletionSuggestionKind, Location;
@@ skipping 483 matching lines @@
           relevance: relevance);
     }
   }
 
   void _addLocalSuggestion_includeReturnValueSuggestions_enumConstant(
       EnumConstantDeclaration constantDeclaration,
       EnumDeclaration enumDeclaration,
       {bool isAbstract: false,
       bool isDeprecated: false,
       int relevance: DART_RELEVANCE_DEFAULT}) {
-    relevance = optype.returnValueSuggestionsFilter(
-        enumDeclaration.element?.type, relevance);
+    ClassElement classElement =
+        resolutionMap.elementDeclaredByEnumDeclaration(enumDeclaration);
+    relevance =
+        optype.returnValueSuggestionsFilter(classElement?.type, relevance);
     if (relevance != null) {
       _addLocalSuggestion_enumConstant(constantDeclaration, enumDeclaration,
           isAbstract: isAbstract,
           isDeprecated: isDeprecated,
           relevance: relevance);
     }
   }
 
   void _addLocalSuggestion_includeTypeNameSuggestions(
       Comment documentationComment,
@@ skipping 82 matching lines @@
       String text = documentationComment.tokens
           .map((Token t) => t.toString())
           .join('\n')
           .replaceAll('\r\n', '\n');
       String doc = removeDartDocDelimiters(text);
       suggestion.docComplete = doc;
       suggestion.docSummary = getDartDocSummary(doc);
     }
   }
 }