code: function cleanupUpdates() {
          Object.keys(_idsToUpdate).forEach(function (id) {
              var installResult = _idsToUpdate[id],
                  keepFile = installResult.keepFile,
                  filename = installResult.localPath;
  
              if (filename && !keepFile) {
                  FileSystem.getFileForPath(filename).unlink();
              }
          });
          _idsToUpdate = {};
      }
docs: Deletes any temporary files left behind by extensions that
  were marked for update.