index: internal item's edje object handling logic changed to improve performance.
index: internal item's edje object handling logic changed to improve performance.

Summary:
The box_clear, box_fill internal functions called when almost every internal chage happend.
(resize, theme apply, item append, item delete etc...)
Then those APIs delete/create item's edje object for all of the items.

It's very not good action for performance.
So, i changed this just edje object box unpack/pack instead of delete/create.

@fix

Test Plan:
Working test on elementary_test
and Call all of the index APIs for check this change.

Reviewers: Hermet, cedric

Reviewed By: cedric

Differential Revision: https://phab.enlightenment.org/D3268

Signed-off-by: Cedric BAIL <240633aa59d25638de9800ef43a88ad2e208d24d@osg.samsung.com>

rvandegrift/elementary,rvandegrift/elementary,rvandegrift/elementary,tasn/elementary,tasn/elementary,rvandegrift/elementary,tasn/elementary,tasn/elementary,tasn/elementary