fix issues caught by analysis_server

test/checker/self_host_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.
 
 /// Tests that run the checker end-to-end using the file system.
 library dev_compiler.test.end_to_end;
 
-import 'dart:io';
 import 'package:cli_util/cli_util.dart' show getSdkDir;
 import 'package:dev_compiler/devc.dart' show Compiler;
 import 'package:dev_compiler/src/options.dart';
-import 'package:path/path.dart' as path;
 import 'package:test/test.dart';
 import '../test_util.dart' show testDirectory;
 
 void main() {
   test('checker can run on itself ', () {
     var options = new CompilerOptions(
         sourceOptions: new SourceResolverOptions(
             entryPointFile: '$testDirectory/all_tests.dart',
             dartSdkPath: getSdkDir().path));
     new Compiler(options).run();
   });
 }