[t:3737], set curr_dsn when deserializing a header

git-svn-id: file:///svn/toku/tokudb@32902 c7de825b-a66e-492c-adef-691d508d4ae1

newbrt/brt-serialize.c

@@ -1681,6 +1681,7 @@ deserialize_brtheader (int fd, struct rbuf *rb, struct brt_header **brth) {
     h->dirty=0;
     h->panic = 0;
     h->panic_string = 0;
+    h->curr_dsn = MIN_DSN+1;
     toku_list_init(&h->live_brts);
     toku_list_init(&h->zombie_brts);
     toku_list_init(&h->checkpoint_before_commit_link);

newbrt/brt.c

@@ -149,6 +149,7 @@ toku_assert_entire_node_in_memory(BRTNODE node) {
 //
 static void
 set_new_DSN_for_node(BRTNODE node, BRT t) {
+    assert(t->h->curr_dsn > MIN_DSN);
     node->dsn = t->h->curr_dsn;
     t->h->curr_dsn++;
 }