Add method field to persistedStateReducer

Summary:
When sending a message from the mobile side, you call something like:

`send(method: string, params: Object)`

But when receiving it in the reducer, you only get the params. Adding method so you can distinguish them.

Reviewed By: passy

Differential Revision: D10447890

fbshipit-source-id: f1fe925e82355866f86b322ecd3c72c604ae86af

src/plugin.js

@@ -126,7 +126,11 @@ export class FlipperPlugin<S = *, A = *, P = *> extends FlipperBasePlugin<
   A,
   P,
 > {
-  static persistedStateReducer: ?(persistedState: P, data: Object) => $Shape<P>;
+  static persistedStateReducer: ?(
+    persistedState: P,
+    method: string,
+    data: Object,
+  ) => $Shape<P>;
   static getActiveNotifications: ?(persistedState: P) => Array<Notification>;
 
   constructor(props: Props<*>) {