[t:4745], only call toku_update_descriptor in deserialize_brtheader_versioned...

[t:4745], only call toku_update_descriptor in deserialize_brtheader_versioned if we are upgrading header

git-svn-id: file:///svn/toku/tokudb@42069 c7de825b-a66e-492c-adef-691d508d4ae1

newbrt/brt-serialize.c

@@ -3059,12 +3059,14 @@ deserialize_brtheader_versioned(int fd, struct rbuf *rb, struct brt_header **brt
     // anymore.  Since the header is going to think it's the current
     // version if it gets written out, we need to write the descriptor in
     // the new format (without those bytes) before that happens.
+    if (version <= BRT_LAYOUT_VERSION_13) {
     int r = toku_update_descriptor(h, &h->cmp_descriptor, fd);
         if (r != 0) {
             errno = r;
             e = DS_ERRNO;
             goto exit;
         }
+    }
 exit:
     if (e != DS_OK && h != NULL) {
         toku_free(h);