LP:933117 - Wrong use_count reported by the range optimizer

The bug #58731 from bugs.mysql.com is reproducible in mariadb-5.2.

When executing the following simple test case

create table t1 (a int, b int, c int, key idx (a,c,b));
insert into t1 values (0,0,0), (0,0,0);
select 1 from t1 force index (idx) where a >=1 and b <= 1 and a=c and c > 1;

the debug build of the mariadb-5.2 server reports:

[Note] Use_count: Wrong count for key at 0x2279948, 0 should be 1.