Don't use dart:io in the pkg/glob tests.

pkg/glob/test/match_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.
 
-import 'dart:io';
-
 import 'package:glob/glob.dart';
 import 'package:path/path.dart' as p;
 import 'package:unittest/unittest.dart';
 
 const ASCII_WITHOUT_SLASH = "\t\n\r !\"#\$%&'()*+`-.0123456789:;<=>?@ABCDEFGHIJ"
     "KLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~";
 
 void main() {
   test("literals match exactly", () {
     expect("foo", contains(new Glob("foo")));
@@ skipping 203 matching lines @@
     });
   });
 
   test("an absolute path can be matched by a relative glob", () {
     var path = p.absolute('foo/bar');
     expect(path, contains(new Glob("foo/bar")));
   });
 
   test("a relative path can be matched by an absolute glob", () {
     var pattern = p.absolute('foo/bar');
-    if (Platform.isWindows) pattern = pattern.replaceAll('\\', '/');
+    if (p.style == p.Style.windows) pattern = pattern.replaceAll('\\', '/');
     expect('foo/bar', contains(new Glob(pattern)));
   });
 
   group("with recursive: true", () {
     var glob = new Glob("foo/bar", recursive: true);
 
     test("still matches basic files", () {
       expect("foo/bar", contains(glob));
     });
 
@@ skipping 36 matching lines @@
     expect(r"http://foo.com/bar",
         contains(new Glob("http://**", context: p.url)));
     expect(r"http://foo.com/bar",
         contains(new Glob("http://foo.com/**", context: p.url)));
 
     expect("/foo/bar", contains(new Glob("/foo/bar", context: p.url)));
     expect("/foo/bar", isNot(contains(new Glob("**", context: p.url))));
     expect("/foo/bar", contains(new Glob("/**", context: p.url)));
   });
 }