Fix a couple broken tests in pub/validator_test.

utils/pub/package.dart

 // Copyright (c) 2012, 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 package;
 
 import 'dart:async';
 
 import '../../pkg/pathos/lib/path.dart' as path;
 
@@ skipping 27 matching lines @@
   /// specified in the pubspec when this package depends on another.
   List<PackageRef> get dependencies => pubspec.dependencies;
 
   /// Returns the path to the README file at the root of the entrypoint, or null
   /// if no README file is found. If multiple READMEs are found, this uses the
   /// same conventions as pub.dartlang.org for choosing the primary one: the
   /// README with the fewest extensions that is lexically ordered first is
   /// chosen.
   Future<String> get readmePath {
     return listDir(dir).then((entries) {
-      var readmes = entries.where((entry) => entry.contains(_README_REGEXP));
+      var readmes = entries.map(path.basename).
+          where((entry) => entry.contains(_README_REGEXP));
       if (readmes.isEmpty) return;
 
-      return readmes.min((readme1, readme2) {
+      return path.join(dir, readmes.min((readme1, readme2) {
         var extensions1 = ".".allMatches(readme1).length;
         var extensions2 = ".".allMatches(readme2).length;
         var comparison = extensions1.compareTo(extensions2);
         if (comparison != 0) return comparison;
         return readme1.compareTo(readme2);
-      });
+      }));
     });
   }
 
   /// Loads the package whose root directory is [packageDir]. [name] is the
   /// expected name of that package (e.g. the name given in the dependency), or
   /// `null` if the package being loaded is the entrypoint package.
   Package.load(String name, String packageDir, SourceRegistry sources)
       : dir = packageDir,
         pubspec = new Pubspec.load(name, packageDir, sources);
 
@@ skipping 138 matching lines @@
 
 class PubspecNameMismatchException implements Exception {
   final String expectedName;
   final String actualName;
 
   PubspecNameMismatchException(this.expectedName, this.actualName);
 
   String toString() => 'The name you specified for your dependency, '
     '"$expectedName", doesn\'t match the name "$actualName" in its pubspec.';
 }