Clean up imports in analysis_server and analyzer_cli (and one missed in analyzer)

pkg/analysis_server/lib/src/services/completion/dart/static_member_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.static_member;
 
 import 'dart:async';
 
 import 'package:analysis_server/src/provisional/completion/dart/completion_dart.dart';
 import 'package:analysis_server/src/services/completion/dart/suggestion_builder.dart';
+import 'package:analyzer/dart/element/element.dart';
+import 'package:analyzer/dart/element/visitor.dart';
 import 'package:analyzer/src/generated/ast.dart';
-import 'package:analyzer/src/generated/element.dart';
 
 import '../../../protocol_server.dart'
     show CompletionSuggestion, CompletionSuggestionKind;
 
 /**
  * A contributor for calculating static member invocation / access suggestions
  * `completion.getSuggestions` request results.
  */
 class StaticMemberContributor extends DartCompletionContributor {
   @override
@@ skipping 111 matching lines @@
   bool _isSpecialEnumField(FieldElement element) {
     Element parent = element.enclosingElement;
     if (parent is ClassElement && parent.isEnum) {
       if (element.name == 'values') {
         return true;
       }
     }
     return false;
   }
 }