[Matrix]: change unit test of mapply_matrix_store.
[Matrix]: change unit test of mapply_matrix_store.

mapply_portion now returns mapply_matrix_store.

icoming/FlashX,zheng-da/FlashX,zheng-da/FlashX,zheng-da/FlashX,icoming/FlashGraph,icoming/FlashGraph,icoming/FlashX,flashxio/FlashX,icoming/FlashGraph,flashxio/FlashX,icoming/FlashX,zheng-da/FlashX,icoming/FlashX,icoming/FlashGraph,flashxio/FlashX,flashxio/FlashX,icoming/FlashGraph,icoming/FlashX,zheng-da/FlashX,flashxio/FlashX,flashxio/FlashX