Summary:
a415ef5552 exposed a bug in `UICollectionView` where its state gets corrupted when deleting the same index path more than once in a single batch update block. This resulted crashes like
```
* thread #1, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x4)
Closes https://github.com/Instagram/IGListKit/pull/657
Reviewed By: jessesquires
Differential Revision: D4913790
Pulled By: rnystrom
fbshipit-source-id: 8f6fcdd2e2438da309fc64ca0ac111b9a0980149