Update edit.importElements response data to support part files

pkg/analysis_server/test/integration/support/integration_test_methods.dart

 // Copyright (c) 2017, 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 file has been automatically generated.  Please do not edit it manually.
 // To regenerate the file, use the script
 // "pkg/analysis_server/tool/spec/generate_files".
 
 /**
  * Convenience methods for running integration tests
@@ skipping 1647 matching lines @@
    * file: FilePath
    *
    *   The file in which the specified elements are to be made accessible.
    *
    * elements: List<ImportedElements>
    *
    *   The elements to be made accessible in the specified file.
    *
    * Returns
    *
-   * edits: List<SourceEdit>
+   * edit: SourceFileEdit
    *
-   *   The edit(s) to be applied in order to make the specified elements
-   *   accessible.
+   *   The edits to be applied in order to make the specified elements
+   *   accessible. The file to be edited will be the defining compilation unit
+   *   of the library containing the file specified in the request, which can
+   *   be different than the file specified in the request if the specified
+   *   file is a part file.
    */
   Future<EditImportElementsResult> sendEditImportElements(
       String file, List<ImportedElements> elements) async {
     var params = new EditImportElementsParams(file, elements).toJson();
     var result = await server.send("edit.importElements", params);
     ResponseDecoder decoder = new ResponseDecoder(null);
     return new EditImportElementsResult.fromJson(decoder, 'result', result);
   }
 
   /**
@@ skipping 546 matching lines @@
         outOfTestExpect(params, isExecutionLaunchDataParams);
         _onExecutionLaunchData.add(
             new ExecutionLaunchDataParams.fromJson(decoder, 'params', params));
         break;
       default:
         fail('Unexpected notification: $event');
         break;
     }
   }
 }