Analysis request `getReachableSources` (#24893).

pkg/analysis_server/lib/plugin/protocol/protocol.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.
 
 /**
  * Support for client code that needs to interact with the requests, responses
  * and notifications that are part of the analysis server's wire protocol.
  */
 library analysis_server.plugin.protocol.protocol;
 
@@ skipping 393 matching lines @@
    * Initialize a newly created instance to represent the
    * GET_NAVIGATION_INVALID_FILE error condition.
    */
   Response.getNavigationInvalidFile(Request request)
       : this(request.id,
             error: new RequestError(
                 RequestErrorCode.GET_NAVIGATION_INVALID_FILE,
                 'Error during `analysis.getNavigation`: invalid file.'));
 
   /**
+   * Initialize a newly created instance to represent the
+   * GET_REACHABLE_SOURCES_INVALID_FILE error condition.
+   */
+  Response.getReachableSourcesInvalidFile(Request request)
+      : this(request.id,
+            error: new RequestError(
+                RequestErrorCode.GET_REACHABLE_SOURCES_INVALID_FILE,
+                'Error during `analysis.getReachableSources`: invalid file.'));
+
+  /**
    * Initialize a newly created instance to represent an error condition caused
    * by an analysis.reanalyze [request] that specifies an analysis root that is
    * not in the current list of analysis roots.
    */
   Response.invalidAnalysisRoot(Request request, String rootPath)
       : this(request.id,
             error: new RequestError(RequestErrorCode.INVALID_ANALYSIS_ROOT,
                 "Invalid analysis root: $rootPath"));
 
   /**
@@ skipping 132 matching lines @@
     jsonObject[ID] = id;
     if (error != null) {
       jsonObject[ERROR] = error.toJson();
     }
     if (_result != null) {
       jsonObject[RESULT] = _result;
     }
     return jsonObject;
   }
 }