Summary: Intention of this change is to simplify and standardise the way top level selection is done. Top level selection is now part of the state, and thus setting it is done in the reducer instead. Reviewed By: antonk52 Differential Revision: D47844742 fbshipit-source-id: 8e5aad8975f0046b85098b988cca40228316c249
flipper-ui-core (TBD)
Flipper's UI, agnostic of Electron vs Browser.