Support for overlay only files in Analysis Server with the new driver.

pkg/analysis_server/test/integration/completion/get_suggestions_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.
 
 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 113 matching lines @@
 
 @reflectiveTest
 class GetSuggestionsTest extends AbstractGetSuggestionsTest {}
 
 @reflectiveTest
 class GetSuggestionsTest_Driver extends AbstractGetSuggestionsTest {
   @override
   bool get enableNewAnalysisDriver => true;
 
   @failingTest
-  test_getSuggestions_onlyOverlay() async {
-    // TimeoutException after 0:00:30.000000: Test timed out after 30 seconds.
-    //return super.test_getSuggestions_onlyOverlay();
-    fail('Test timed out');
-  }
-
-  @failingTest
   test_getSuggestions_sourceMissing_noWait() {
     //  Expected: same instance as 'exception from server'
     //    Actual: CompletionGetSuggestionsResult:<{"id":"0"}>
     return super.test_getSuggestions_sourceMissing_noWait();
   }
 }