Use record for CommandHandler.infer_type input
Use record for CommandHandler.infer_type input

Summary: This replaces the tuple-input to `infer_type` with a record.

Reviewed By: dsainati1

Differential Revision: D19269452

fbshipit-source-id: 382b4b7ae7328a46ccfd619f0a6e27fca9fe076e

samwgoldman/flow,facebook/flow,samwgoldman/flow,mroch/flow,mroch/flow,facebook/flow,samwgoldman/flow,facebook/flow,samwgoldman/flow,facebook/flow,mroch/flow,mroch/flow,samwgoldman/flow,mroch/flow,facebook/flow,mroch/flow,mroch/flow,facebook/flow,samwgoldman/flow,facebook/flow,samwgoldman/flow