Add copyright header to generated analyzer files.

pkg/analyzer/lib/src/generated/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.
+
 // This code was auto-generated, is not intended to be edited, and is subject to
 // significant change. Please see the README file for more information.
 
 library engine.index;
 
 import 'dart:collection' show Queue;
 import 'java_core.dart';
 import 'source.dart';
 import 'scanner.dart' show Token;
 import 'ast.dart';
@@ skipping 2663 matching lines @@
    * element are available. For example, if the element is a field and the relationship is the
    * is-referenced-by relationship, then this method will be invoked with each location at which the
    * field is referenced.
    *
    * @param element the [Element] that has the relationship with the locations
    * @param relationship the relationship between the given element and the locations
    * @param locations the locations that were found
    */
   void hasRelationships(Element element, Relationship relationship, List<Location> locations);
 }