Summary:
Currently, `EventListener` in listner.h only have callback functions for file read and write. One may favor extended callback functions for more file I/O operations like flush, sync and close. This PR tries to add those interface and have them called when appropriate throughout the code base.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7055
Test Plan:
Write an experimental listener with those new callback functions with log output in them; run experiments and check logs to see those functions are actually called.
Default test suits `make check` should also be included.
Reviewed By: riversand963
Differential Revision: D22380624
Pulled By: roghnin
fbshipit-source-id: 4121491d45c2c2aae8c255e7998090559a241c6a
226d1f9c73