genlist : fixing wrong item realize bug when block is changed

genlist : fixing wrong item realize bug when block is changed

Summary :
If current realized item is changed to another block which
was unrealized, item still stay in realized states because
new block is unrealized.
so when adding item to new block, adding realized state check
to change block realized state correctly.

Test Plan :
The issue is happen in eflete edc group list view.
when you expand and contract the tree view, if child is
bigger then block size, items under the current tree still
floating on the child items.

Signed-off-by: SangHyeon Lee <sh10233.lee@samsung.com>