fixed var_samp printing (BUG#10651)

mysql-test/r/view.result:
  Using var_samp with view (BUG#10651)
mysql-test/t/view.test:
  Using var_samp with view (BUG#10651)
sql/item_sum.h:
  fixed var_samp printing

mysql-test/r/view.result

@@ -1850,3 +1850,10 @@ SELECT * FROM v1;
 SUBSTRING_INDEX("dkjhgd:kjhdjh", ":", 1)
 dkjhgd
 drop view v1;
+create table t1 (s1 int);
+create view v1 as select var_samp(s1) from t1;
+show create view v1;
+View	Create View
+v1	CREATE ALGORITHM=UNDEFINED VIEW `test`.`v1` AS select var_samp(`test`.`t1`.`s1`) AS `var_samp(s1)` from `test`.`t1`
+drop view v1;
+drop table t1;

mysql-test/t/view.test

@@ -1696,3 +1696,13 @@ drop view v1;
 CREATE VIEW v1 AS SELECT SUBSTRING_INDEX("dkjhgd:kjhdjh", ":", 1);
 SELECT * FROM v1;
 drop view v1;
+
+#
+# Using var_samp with view (BUG#10651)
+#
+create table t1 (s1 int);
+create view v1 as select var_samp(s1) from t1;
+show create view v1;
+drop view v1;
+drop table t1;
+

sql/item_sum.h

@@ -479,7 +479,8 @@ class Item_sum_variance : public Item_sum_num
   Item *result_item(Field *field)
   { return new Item_variance_field(this); }
   void no_rows_in_result() {}
-  const char *func_name() const { return "variance("; }
+  const char *func_name() const
+    { return sample ? "var_samp(" : "variance("; }
   Item *copy_or_same(THD* thd);
   Field *create_tmp_field(bool group, TABLE *table, uint convert_blob_length);
   enum Item_result result_type () const { return hybrid_type; }