Remove more libraries directives from server

pkg/analysis_server/lib/src/search/element_references.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 search.element_references;
-
 import 'dart:async';
 
 import 'package:analysis_server/src/protocol_server.dart'
     show SearchResult, newSearchResult_fromMatch;
 import 'package:analysis_server/src/services/search/hierarchy.dart';
 import 'package:analysis_server/src/services/search/search_engine.dart';
 import 'package:analyzer/dart/element/element.dart';
 
 /**
  * A computer for `search.findElementReferences` request results.
@@ skipping 69 matching lines @@
     return newSearchResult_fromMatch(match);
   }
 
   static bool _isMemberElement(Element element) {
     if (element is ConstructorElement) {
       return false;
     }
     return element.enclosingElement is ClassElement;
   }
 }