Added a class Frame_unbounded_following_set_count_special, which is required to ignore all the null values while calculating the number of rows in the partition
Added a class Frame_unbounded_following_set_count_special, which is required to ignore
all the null values while calculating the number of rows in the partition

natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2