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

pkg/analysis_server/lib/src/domains/analysis/implemented_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 domains.analysis.implemented_dart;
 
 import 'package:analysis_server/src/protocol_server.dart' as protocol;
 import 'package:analysis_server/src/services/search/hierarchy.dart';
 import 'package:analysis_server/src/services/search/search_engine.dart';
-import 'package:analyzer/src/generated/element.dart';
+import 'package:analyzer/dart/element/element.dart';
 
 class ImplementedComputer {
   final SearchEngine searchEngine;
   final CompilationUnitElement unitElement;
 
   List<protocol.ImplementedClass> classes = <protocol.ImplementedClass>[];
   List<protocol.ImplementedMember> members = <protocol.ImplementedMember>[];
 
   Set<ClassElement> subtypes;
 
@@ skipping 61 matching lines @@
    */
   static bool _isStatic(Element element) {
     if (element is ExecutableElement) {
       return element.isStatic;
     } else if (element is PropertyInducingElement) {
       return element.isStatic;
     }
     return false;
   }
 }