Summary:
Several functions of UniversalCompactionPicker share most of the parameters. Move these functions to a class with those shared arguments as class members. Hopefully this will make code slightly easier to maintain.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5639
Test Plan: Run all existing test.
Differential Revision: D16996403
fbshipit-source-id: fffafd1897ab132b420b1dec073542cffb5c44de