Make certain generated constructor parameters optional.

pkg/analysis_server/test/edit/assists_test.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 test.edit.assists;
 
 import 'dart:async';
 
 import 'package:analysis_server/src/edit/edit_domain.dart';
 import 'package:analysis_server/src/protocol.dart';
@@ skipping 23 matching lines @@
   void prepareAssistsAt(int offset, int length) {
     Request request = new EditGetAssistsParams(testFile, offset,
         length).toRequest('0');
     Response response = handleSuccessfulRequest(request);
     var result = new EditGetAssistsResult.fromResponse(response);
     List<SourceChange> sourceChangeList = result.assists;
     // TODO(scheglov) consider using generated classes and decoders
     changes = sourceChangeList.map((SourceChange sourceChange) {
       Change change = new Change(sourceChange.message);
       sourceChange.edits.forEach((SourceFileEdit sourceFileEdit) {
-        SourceFileEdit fileEdit = new SourceFileEdit(sourceFileEdit.file,
-            <SourceEdit>[]);
+        SourceFileEdit fileEdit = new SourceFileEdit(sourceFileEdit.file);
         change.fileEdits.add(fileEdit);
         fileEdit.edits.addAll(sourceFileEdit.edits);
       });
       return change;
     }).toList();
   }
 
   @override
   void setUp() {
     super.setUp();
@@ skipping 61 matching lines @@
       if (change.message == message) {
         String resultCode =
             SourceEdit.applySequence(testCode, change.fileEdits[0].edits);
         expect(resultCode, expectedCode);
         return;
       }
     }
     fail("Expected to find |$message| in\n" + changes.join('\n'));
   }
 }