Merge change 1685 into donut

* changes:
  Remove unnecessary code.

core/java/android/backup/FileBackupHelper.java

@@ -60,9 +60,6 @@ public class FileBackupHelper {
         if (newStateFd == null) {
             throw new NullPointerException();
         }
-        if (files == null) {
-            throw new NullPointerException();
-        }
 
         int err = performBackup_native(basePath, oldStateFd, data.fd, newStateFd, files);