Summary:
Make the CompactOnDeletionCollectorFactory class public, and provide
methods to update the window size and deletion trigger params. These
will take effect on subsequent created SST files.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4403
Differential Revision: D9976857
Pulled By: anand1976
fbshipit-source-id: 31dbf0511c12fa2bb9b2a7ba620079e0ee09cf48