Summary:
This is needed in preperation for the next diff where we will introduce an observer per litho view. Without batching we end up with really poor performance for a few reasons:
1. There are some operations on the desktop plugin that are o(nodes) so even sending small batches
2. Flipper isnt really a high performance message bus, it seems to prefer fewer larger messages
3. Queuing time on the client builds up as you spend more time waiting on the socket
In a future diff will address:
The name of subtree update event. It should probably be called something like FrameUpdate since they are always full frames
The performance monitoring, will more to timing methods and summing the result rather than the current appraoch of time markers
Reviewed By: lblasa
Differential Revision: D42453229
fbshipit-source-id: eda9830b4420e82874717cc69b241e1689f20029
b5392fb818