Add union types to the analysis server API spec.

pkg/analysis_server/test/integration/integration_test_methods.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 file has been automatically generated.  Please do not edit it manually.
 // To regenerate the file, use the script
 // "pkg/analysis_server/spec/generate_files".
 
 /**
  * Convenience methods for running integration tests
@@ skipping 384 matching lines @@
   /**
    * Update the content of one or more files. Files that were previously
    * updated but not included in this update remain unchanged. This effectively
    * represents an overlay of the filesystem. The files whose content is
    * overridden are therefore seen by server as being files with the given
    * content, even if the files do not exist on the filesystem or if the file
    * path represents the path to a directory on the filesystem.
    *
    * Parameters
    *
-   * files ( Map<FilePath, object> )
+   * files ( Map<FilePath, AddContentOverlay | ChangeContentOverlay |
+   * RemoveContentOverlay> )
    *
    *   A table mapping the files whose content has changed to a description of
-   *   the content change. Each value should be one of the following types:
-   *   AddContentOverlay, ChangeContentOverlay, or RemoveContentOverlay.
+   *   the content change.
    */
-  Future sendAnalysisUpdateContent(Map<String, Map<String, dynamic>> files, {bool checkTypes: true}) {
+  Future sendAnalysisUpdateContent(Map<String, Object> files, {bool checkTypes: true}) {
     Map<String, dynamic> params = {};
     params["files"] = files;
     if (checkTypes) {
       expect(params, isAnalysisUpdateContentParams);
     }
     return server.send("analysis.updateContent", params)
         .then((result) {
       if (checkTypes) {
         expect(result, isAnalysisUpdateContentResult);
       }
@@ skipping 1019 matching lines @@
       case "debug.launchData":
         expect(params, isDebugLaunchDataParams);
         _onDebugLaunchData.add(params);
         break;
       default:
         fail('Unexpected notification: $event');
         break;
     }
   }
 }