[Sprint/PinkPanther] (feat) scroll to index after remind from subscribed list

To test before this feat:

1. in subscribed newsfeed list scroll a bit then remind a long post
2. after remind, and see the newsfeed list again, it can be seen that the list move a bit to top. this happens because of the new post (remind) that is appended to the list.

To test after apply feat:

1. in subscribed newsfeed list scroll a bit then remind a long post
2. after remind, and see the newssfed list again, it can be seen that the list move a bit down and the just reminded post is still visible