Summary:
The callback `dispatchEvent` is called asynchronously on the JavaScript thread, so all data it uses must be copied to the lambda. To work around this constraint we use a shared pointer for the counter.
Changelog: [Internal] Fabric-specific internal change.
Reviewed By: sammy-SC
Differential Revision: D24598840
fbshipit-source-id: fb5581858d54dc806863caf0c7c4f612ed6046e2
Valentin Shergin
306a8adade