Fix context comparisons

pkg/analyzer/test/file_system/memory_file_system_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.
 
 library analyzer.test.file_system.memory_file_system_test;
 
 import 'dart:async';
 import 'dart:core';
 
 import 'package:analyzer/file_system/file_system.dart';
@@ skipping 447 matching lines @@
     source = file.createSource();
   }
 
   void test_contents() {
     TimestampedData<String> contents = source.contents;
     expect(contents.data, 'library test;');
   }
 
   void test_encoding() {
     String expected = 'file:///foo/test.dart';
-    if (provider.pathContext == windows) {
+    if (provider.pathContext.style == windows.style) {
       expected = 'file:///C:/foo/test.dart';
     }
     expect(source.encoding, expected);
   }
 
   void test_equals_false_differentFile() {
     File fileA = provider.newFile(provider.convertPath('/foo/a.dart'), '');
     File fileB = provider.newFile(provider.convertPath('/foo/b.dart'), '');
     Source sourceA = fileA.createSource();
     Source sourceB = fileB.createSource();
@@ skipping 66 matching lines @@
   }
 
   void test_contents() {
     expect(() {
       source.contents;
     }, throwsA(_isFileSystemException));
   }
 
   void test_encoding() {
     String expected = 'file:///foo/test.dart';
-    if (provider.pathContext == windows) {
+    if (provider.pathContext.style == windows.style) {
       expected = 'file:///C:/foo/test.dart';
     }
     expect(source.encoding, expected);
   }
 
   void test_exists() {
     expect(source.exists(), isFalse);
   }
 
   void test_fullName() {
@@ skipping 204 matching lines @@
     return new Future.delayed(Duration.ZERO, computation);
   }
 
   _watchingFolder(String path, test(List<WatchEvent> changesReceived)) {
     Folder folder = provider.getResource(path);
     var changesReceived = <WatchEvent>[];
     folder.changes.listen(changesReceived.add);
     return test(changesReceived);
   }
 }