Merge a compile fix.

.bzr-mysql/default.conf

 [MYSQL]
 post_commit_to = "commits@lists.mysql.com"
 post_push_to = "commits@lists.mysql.com"
-tree_name = "mysql-5.1-bugteam"
+tree_name = "mysql-5.1"

mysys/mf_keycache.c

@@ -1729,7 +1729,7 @@ static BLOCK_LINK *find_key_block(KEY_CACHE *keycache,
       - block assigned but not yet read from file (invalid data).
   */
 
-#if THREAD
+#ifdef THREAD
   if (keycache->in_resize)
   {
     /* This is a request during a resize operation */