Switch analyzer_cli to 'package:test'.

pkg/analyzer_cli/test/driver_test.dart

 // Copyright (c) 2015, 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 analyzer_cli.test.driver;
 
 import 'dart:io';
 
 import 'package:analyzer/error/error.dart';
 import 'package:analyzer/plugin/options.dart';
 import 'package:analyzer/source/analysis_options_provider.dart';
 import 'package:analyzer/source/error_processor.dart';
 import 'package:analyzer/src/error/codes.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/services/lint.dart';
 import 'package:analyzer/src/task/options.dart';
 import 'package:analyzer_cli/src/driver.dart';
 import 'package:analyzer_cli/src/options.dart';
 import 'package:path/path.dart' as path;
 import 'package:plugin/plugin.dart';
-import 'package:unittest/unittest.dart';
+import 'package:test/test.dart';
 import 'package:yaml/src/yaml_node.dart';
 
 import 'utils.dart';
 
 main() {
   StringSink savedOutSink, savedErrorSink;
   int savedExitCode;
   ExitHandler savedExitHandler;
 
   /// Base setup.
@@ skipping 12 matching lines @@
     outSink = savedOutSink;
     errorSink = savedErrorSink;
     exitCode = savedExitCode;
     exitHandler = savedExitHandler;
   }
 
   setUp(() => _setUp());
 
   tearDown(() => _tearDown());
 
-  initializeTestEnvironment();
-
   group('Driver', () {
     group('options', () {
       test('custom processor', () {
         Driver driver = new Driver();
         TestProcessor processor = new TestProcessor();
         driver.userDefinedPlugins = [new TestPlugin(processor)];
         driver.start([
           '--options',
           path.join(testDirectory, 'data/test_options.yaml'),
           path.join(testDirectory, 'data/test_file.dart')
@@ skipping 470 matching lines @@
     this.options = options;
   }
 }
 
 class TestSource implements Source {
   TestSource();
 
   @override
   noSuchMethod(Invocation invocation) => super.noSuchMethod(invocation);
 }