Use Asynclog as fallback if failing to write to Axon
Use Asynclog as fallback if failing to write to Axon

Summary: As title

Reviewed By: stuclar

Differential Revision: D39661687

fbshipit-source-id: 91523f4778985924c207c93f079d7a537f7fddec

facebook/mcrouter,facebook/mcrouter,facebook/mcrouter,facebook/mcrouter