Summary:
The current event label used the event type. The type in itself can have this shape:
`ck:willMountComponent`
The event name is just 'willMountComponent'.
So, extract that piece of data instead.
Reviewed By: aigoncharov
Differential Revision: D43983728
fbshipit-source-id: e232b59cfe3eb0710e56fc9ba7f94b644b07ee74