MDEV-38068 Query doesn't delete all data it should after update to 11.8.4

a fix for MDEV-15990 has unintentionally added
HA_EXTRA_REMEMBER_POS/HA_EXTRA_RESTORE_POS on the code path for normal,
not versioned, deletes.

Let's restore the old logic.

followup for 8001679

Author: vuvova

mysql-test/main/delete.result

@@ -779,6 +779,22 @@ id
 Warnings:
 Warning	4207	Index hints are ignored because they are incompatible with RETURNING clause
 drop table t2;
-#
 # End of 11.4 test
 #
+# MDEV-38068 Query doesn't delete all data it should after update to 11.8.4
+#
+create table t1 (id varchar(32), d1 char, key (id), key (d1)) engine=myisam;
+insert into t1 values ('1','A'), ('1','B'), ('1','C'), ('2','D'), ('2','E');
+select count(*) from t1;
+count(*)
+5
+need "range" below
+explain delete from t1 where id = '1';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	range	id	id	131	NULL	3	Using where
+delete from t1 where id = '1';
+select count(*) from t1;
+count(*)
+2
+drop table t1;
+# End of 11.8 test

mysql-test/main/delete.test

@@ -825,6 +825,18 @@ DELETE FROM t2 ignore index(primary) ORDER BY (id) LIMIT 2 RETURNING id;
 
 drop table t2;
 
---echo #
 --echo # End of 11.4 test
+
 --echo #
+--echo # MDEV-38068 Query doesn't delete all data it should after update to 11.8.4
+--echo #
+create table t1 (id varchar(32), d1 char, key (id), key (d1)) engine=myisam;
+insert into t1 values ('1','A'), ('1','B'), ('1','C'), ('2','D'), ('2','E');
+select count(*) from t1;
+--echo need "range" below
+explain delete from t1 where id = '1';
+delete from t1 where id = '1';
+select count(*) from t1;
+drop table t1;
+
+--echo # End of 11.8 test

sql/sql_delete.cc

@@ -312,18 +312,20 @@ template <bool replace>
 int TABLE::delete_row(bool treat_versioned)
 {
   int err= 0;
+  bool remembered_pos= false;
   uchar *del_buf= record[replace ? 1 : 0];
   bool delete_row= !treat_versioned
                    || in_use->lex->vers_conditions.delete_history
                    || versioned(VERS_TRX_ID)
                    || !vers_end_field()->is_max(
                            vers_end_field()->ptr_in_record(del_buf));
 
-  if ((err= file->extra(HA_EXTRA_REMEMBER_POS)))
-    return err;
-
   if (!delete_row)
   {
+    if ((err= file->extra(HA_EXTRA_REMEMBER_POS)))
+      return err;
+    remembered_pos= true;
+
     if (replace)
     {
       store_record(this, record[2]);
@@ -370,7 +372,8 @@ int TABLE::delete_row(bool treat_versioned)
   if (delete_row)
     err= file->ha_delete_row(del_buf);
 
-  (void) file->extra(HA_EXTRA_RESTORE_POS);
+  if (remembered_pos)
+    (void) file->extra(HA_EXTRA_RESTORE_POS);
 
   return err;
 }