track onMessage performance
track onMessage performance

Summary: Tracking the time of onMessage callback

Reviewed By: passy

Differential Revision: D15536546

fbshipit-source-id: 9e93c11555a0a045ef60355ec1d0c6ca7cd49cdd

facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper