DB-829 ignore read uncommitted errors when querying tokudb_fractal_tree_info

mysql-test/suite/tokudb.bugs/r/tokudb718.result

@@ -3,7 +3,8 @@ drop table if exists t;
 create table t (id int primary key);
 begin;
 insert into t values (1),(2);
-select * from information_schema.tokudb_fractal_tree_info;
-ERROR HY000: Got error -30994 from storage engine
+select dictionary_name from information_schema.tokudb_fractal_tree_info;
+dictionary_name
+./test/t-status
 commit;
 drop table t;

mysql-test/suite/tokudb.bugs/t/tokudb718.test

@@ -7,7 +7,6 @@ enable_warnings;
 create table t (id int primary key);
 begin;
 insert into t values (1),(2);
---error 1030
-select * from information_schema.tokudb_fractal_tree_info;
+select dictionary_name from information_schema.tokudb_fractal_tree_info;
 commit;
 drop table t;

storage/tokudb/hatoku_hton.cc

@@ -1711,6 +1711,8 @@ static int tokudb_fractal_tree_info(TABLE *table, THD *thd) {
         error = tmp_cursor->c_get(tmp_cursor, &curr_key, &curr_val, DB_NEXT);
         if (!error) {
             error = tokudb_report_fractal_tree_info_for_db(&curr_key, &curr_val, table, thd);
+            if (error)
+                error = 0; // ignore read uncommitted errors
         }
         if (!error && thd_killed(thd))
             error = ER_QUERY_INTERRUPTED;