Backport into MariaDB-5.2 the following:

WL#2474 "Multi Range Read: Change the default MRR implementation to implement new MRR interface"
WL#2475 "Batched range read functions for MyISAM/InnoDb"
        "Index condition pushdown for MyISAM/InnoDB"
- Fix valgrind failures

sql/handler.h

@@ -1381,7 +1381,9 @@ public:
     ref_length(sizeof(my_off_t)),
     ft_handler(0), inited(NONE),
     locked(FALSE), implicit_emptied(0),
-    pushed_cond(0), next_insert_id(0), insert_id_for_cur_row(0),
+    pushed_cond(0), pushed_idx_cond(NULL),
+    pushed_idx_cond_keyno(MAX_KEY),
+    next_insert_id(0), insert_id_for_cur_row(0),
     auto_inc_intervals_count(0)
     {
       reset_statistics();