Switch the default from non-driver to driver in several tests

pkg/analysis_server/test/services/index/index_unit_test.dart

 // Copyright (c) 2016, 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 'dart:async';
 import 'dart:convert';
 
 import 'package:analysis_server/src/services/index/index_unit.dart';
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/element/element.dart';
@@ skipping 24 matching lines @@
     return '(unit=$unitElement; offset=$offset; length=$length;'
         ' isQualified=$isQualified)';
   }
 }
 
 @reflectiveTest
 class PackageIndexAssemblerTest extends AbstractSingleUnitTest {
   PackageIndex packageIndex;
   UnitIndex unitIndex;
 
+  @override
+  bool get enableNewAnalysisDriver => false;
+
   _ElementIndexAssert assertThat(Element element) {
     List<_Relation> relations = _getElementRelations(element);
     return new _ElementIndexAssert(this, element, relations);
   }
 
   _NameIndexAssert assertThatName(String name) {
     return new _NameIndexAssert(this, name);
   }
 
   CompilationUnitElement importedUnit({int index: 0}) {
@@ skipping 1278 matching lines @@
   final bool isQualified;
 
   _Relation(this.kind, this.offset, this.length, this.isQualified);
 
   @override
   String toString() {
     return '_Relation{kind: $kind, offset: $offset, length: $length, '
         'isQualified: $isQualified}';
   }
 }