Use shorter DartElementLocation.

pkg/analysis_server/lib/src/services/index/index.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 services.index;
 
 import 'dart:async';
 
 import 'package:analyzer/src/generated/ast.dart';
 import 'package:analyzer/src/generated/element.dart';
@@ skipping 303 matching lines @@
  * An [Element] which is used to index references to the name without specifying
  * a concrete kind of this name - field, method or something else.
  */
 class NameElement extends ElementImpl {
   NameElement(String name) : super("name:${name}", -1);
 
   @override
   ElementKind get kind => ElementKind.NAME;
 
   @override
+  bool operator ==(Object other) {
+    return other is NameElement && other.name == name;
+  }
+
+  @override
   accept(ElementVisitor visitor) => null;
 }
 
 
 /**
  * Relationship between an element and a location. Relationships are identified
  * by a globally unique identifier.
  */
 class Relationship {
   /**
@@ skipping 36 matching lines @@
   static final UniverseElement INSTANCE = new UniverseElement._();
 
   UniverseElement._() : super("--universe--", -1);
 
   @override
   ElementKind get kind => ElementKind.UNIVERSE;
 
   @override
   accept(ElementVisitor visitor) => null;
 }