Make the analysis server integration tests driver only.

pkg/analysis_server/test/integration/edit/get_assists_test.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.
 
 import 'package:analysis_server/plugin/protocol/protocol.dart';
 import 'package:test/test.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
 import '../integration_tests.dart';
 
@@ skipping 28 matching lines @@
         change.message == "Add explicit 'show' combinator");
     expect(change.edits, hasLength(1));
     expect(change.edits.first.edits, hasLength(1));
     SourceEdit edit = change.edits.first.edits.first;
     text = text.replaceRange(edit.offset, edit.end, edit.replacement);
     writeFile(pathname, text);
 
     await analysisFinished;
     expect(currentAnalysisErrors[pathname], isEmpty);
   }
-
-  @override
-  bool get enableNewAnalysisDriver => true;
 }