Get binstubs working on Windows.

sdk/lib/_internal/pub/test/global/binstubs/name_collision_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 'package:scheduled_test/scheduled_stream.dart';
 import 'package:scheduled_test/scheduled_test.dart';
 
 import '../../descriptor.dart' as d;
 import '../../test_pub.dart';
+import 'utils.dart';
 
 main() {
   initConfig();
   integration("does not overwrite an existing binstub", () {
     d.dir("foo", [
       d.pubspec({
         "name": "foo",
         "executables": {
           "foo": "foo",
           "collide1": "foo",
@@ skipping 24 matching lines @@
     var pub = startPub(args: ["global", "activate", "-spath", "../bar"]);
     pub.stdout.expect(consumeThrough("Installed executable bar."));
     pub.stderr.expect("Executable collide1 was already installed from foo.");
     pub.stderr.expect("Executable collide2 was already installed from foo.");
     pub.stderr.expect("Deactivate the other package(s) or activate bar using "
         "--overwrite.");
     pub.shouldExit();
 
     d.dir(cachePath, [
       d.dir("bin", [
-        d.matcherFile("foo", contains("foo:foo")),
-        d.matcherFile("bar", contains("bar:bar")),
-        d.matcherFile("collide1", contains("foo:foo")),
-        d.matcherFile("collide2", contains("foo:foo"))
+        d.matcherFile(binStubName("foo"), contains("foo:foo")),
+        d.matcherFile(binStubName("bar"), contains("bar:bar")),
+        d.matcherFile(binStubName("collide1"), contains("foo:foo")),
+        d.matcherFile(binStubName("collide2"), contains("foo:foo"))
       ])
     ]).validate();
   });
 }