Build fix.  [TBR] (Fix dart-lang/package_config#9)
diff --git a/pkgs/package_config/lib/src/packages_impl.dart b/pkgs/package_config/lib/src/packages_impl.dart
index 9563762..6d88a65 100644
--- a/pkgs/package_config/lib/src/packages_impl.dart
+++ b/pkgs/package_config/lib/src/packages_impl.dart
@@ -21,7 +21,7 @@
                                   'No package named "$packageName"');
   }
 
-  Iterable<String> get packages => new Iterable<String>.empty();
+  Iterable<String> get packages => new Iterable<String>.generate(0);
 
   Map<String, Uri> asMap() => const<String,Uri>{};
 }