Fix context comparisons

pkg/analyzer/lib/file_system/memory_file_system.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.file_system.memory_file_system;
 
 import 'dart:async';
 import 'dart:collection';
 import 'dart:convert';
 import 'dart:core';
@@ skipping 32 matching lines @@
   @override
   pathos.Context get pathContext => _pathContext;
 
   /**
    * Convert the given posix [path] to conform to this provider's path context.
    *
    * This is a utility method for testing; paths passed in to other methods in
    * this class are never converted automatically.
    */
   String convertPath(String path) {
-    if (pathContext == pathos.windows &&
+    if (pathContext.style == pathos.windows.style &&
         path.startsWith(pathos.posix.separator)) {
       path = r'C:' +
           path.replaceAll(pathos.posix.separator, pathos.windows.separator);
     }
     return path;
   }
 
   /**
    * Delete the file with the given path.
    */
@@ skipping 270 matching lines @@
   File renameSync(String newPath) {
     throw new FileSystemException(path, 'File could not be renamed');
   }
 
   @override
   File resolveSymbolicLinksSync() {
     return throw new FileSystemException(path, "File does not exist");
   }
 
   @override
-  Uri toUri() =>
-      new Uri.file(path, windows: _provider.pathContext == pathos.windows);
-
-  @override
   void writeAsBytesSync(List<int> bytes) {
     throw new FileSystemException(path, 'File could not be written');
   }
 
   @override
   void writeAsStringSync(String content) {
     throw new FileSystemException(path, 'File could not be written');
   }
 }
 
@@ skipping 201 matching lines @@
     }
     return path == other.path;
   }
 
   @override
   String toString() => path;
 
   @override
   Uri toUri() => _provider.pathContext.toUri(path);
 }