Pub: fix the 'system_cache' library

utils/pub/system_cache.dart

Index: utils/pub/system_cache.dart
diff --git a/utils/pub/system_cache.dart b/utils/pub/system_cache.dart
index fd9035417ebe4c31d0d3fc26370dca3735c332b8..24db19de99a9be705a71f6f3d48043af228b7414 100644
--- a/utils/pub/system_cache.dart
+++ b/utils/pub/system_cache.dart
@@ -9,6 +9,7 @@
 #import('source.dart');
 #import('source_registry.dart');
 #import('utils.dart');
+#import('version.dart');
 
 /**
  * The system-wide cache of installed packages.
@@ -60,7 +61,7 @@ class SystemCache {
           // TODO(rnystrom): Once there are cached packages and this path is
           // being used, figure out how version numbers should be acquired.
           return subpaths.map((subpath) =>
-            new PackageId(basename(subpath), source, Version.none));
+            new PackageId(source, Version.none, basename(subpath)));
         });
       });
       return Futures.wait(sources).transform(flatten);