set_var.cc:

  Make query_cache_wlock_invalidate show up in SHOW VARIABLES.
  (Sanja agrees that it should show up, has seen the patch, and
  agrees that it's correct.)

sql/set_var.cc

@@ -769,6 +769,8 @@ struct show_var_st init_vars[]= {
    SHOW_SYS},
   {sys_query_cache_size.name, (char*) &sys_query_cache_size,	    SHOW_SYS},
   {sys_query_cache_type.name, (char*) &sys_query_cache_type,        SHOW_SYS},
+  {sys_query_cache_wlock_invalidate.name,
+   (char *) &sys_query_cache_wlock_invalidate, SHOW_SYS},
 #endif /* HAVE_QUERY_CACHE */
   {sys_query_prealloc_size.name, (char*) &sys_query_prealloc_size,  SHOW_SYS},
   {sys_range_alloc_block_size.name, (char*) &sys_range_alloc_block_size,