suppress ENOENT on metadata when restoring archived files

lib/storage/file.js

@@ -722,9 +722,9 @@ var unarchiveChannel = function (env, channelName, cb) {
         // restore the metadata log
         Fse.move(archiveMetadataPath, metadataPath, w(function (err) {
             // if there's nothing to move, you're done.
-            /*if (err && err.code === 'ENOENT') {
+            if (err && err.code === 'ENOENT') {
                 return CB();
-            }*/ // XXX make sure removing this part won't break anything
+            }
             // call back with an error if something goes wrong
             if (err) {
                 w.abort();