wangle/channel/EventBaseHandler.h: fix missing includes and deps
wangle/channel/EventBaseHandler.h: fix missing includes and deps

Reviewed By: yfeldblum

Differential Revision: D9135360

fbshipit-source-id: 75cc71f808c06ee1c0631d0c5b74783b22179773

facebook/wangle,facebook/wangle,facebook/wangle