Return RequestErrorCode.NO_INDEX_GENERATED for search/refactoring requests.

pkg/analysis_server/lib/src/get_handler.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 analysis_server.src.get_handler;
 
 import 'dart:async';
 import 'dart:collection';
 import 'dart:convert';
 import 'dart:io';
@@ skipping 849 matching lines @@
   /**
    * Return a response containing information about elements with the given
    * name.
    */
   Future _returnIndexElementByName(HttpRequest request) async {
     AnalysisServer analysisServer = _server.analysisServer;
     if (analysisServer == null) {
       return _returnFailure(request, 'Analysis server not running');
     }
     Index index = analysisServer.index;
+    if (index == null) {
+      return _returnFailure(request, 'Indexing is disabled');
+    }
     String name = request.uri.queryParameters[INDEX_ELEMENT_NAME];
     if (name == null) {
       return _returnFailure(
           request,
           'Query parameter $INDEX_ELEMENT_NAME required');
     }
     if (index is LocalIndex) {
       Map<List<String>, List<InspectLocation>> relations =
           await index.findElementsByName(name);
       _writeResponse(request, (StringBuffer buffer) {
@@ skipping 744 matching lines @@
    * 'error'.
    */
   static String makeLink(String path, Map<String, String> params,
       String innerHtml, [bool hasError = false]) {
     Uri uri = new Uri(path: path, queryParameters: params);
     String href = HTML_ESCAPE.convert(uri.toString());
     String classAttribute = hasError ? ' class="error"' : '';
     return '<a href="$href"$classAttribute>$innerHtml</a>';
   }
 }