Merge adventure.(none):/home/thek/Development/cpp/bug27792/my41-bug27792

into  adventure.(none):/home/thek/Development/cpp/bug27792/my50-bug27792


sql/mysql_priv.h:
  Auto merged
mysql-test/r/query_cache.result:
  Null merge
mysql-test/t/query_cache.test:
  Null merge
sql/set_var.cc:
  Null merge
sql/sql_cache.cc:
  Null merge

sql/mysql_priv.h

@@ -642,6 +642,7 @@ struct Query_cache_query_flags
   ulong sql_mode;
   ulong max_sort_length;
   ulong group_concat_max_len;
+  ulong default_week_format;
   MY_LOCALE *lc_time_names;
 };
 #define QUERY_CACHE_FLAGS_SIZE sizeof(Query_cache_query_flags)