Include ID for logged-in User

Summary: Adding id field for the currently logged in user in the store's state

Reviewed By: passy

Differential Revision: D20928642

fbshipit-source-id: eff5373bd88ed8fd228193b47649f586cf20b585

desktop/app/src/reducers/user.tsx

@@ -13,6 +13,7 @@ export const USER_UNAUTHORIZED = 'Unauthorized.';
 export const USER_NOT_SIGNEDIN = 'Not signed in.';
 
 export type User = {
+  id?: string;
   name?: string;
   profile_picture?: {
     uri: string;