Wait for client to initliaze on startup deep link

Summary: We were incorrectly assuming a client did not support a plugin because it was not fully initialized. This issue was only apparant on start deep links

Reviewed By: mweststrate

Differential Revision: D40477503

fbshipit-source-id: 5fd9db765f559b8eb80cc3680ee694dfd2cf9a37

desktop/flipper-frontend-core/src/AbstractClient.tsx

@@ -50,6 +50,7 @@ export type RequestMetadata = {
 
 export interface ClientConnection {
   send(data: any): void;
+
   sendExpectResponse(data: any): Promise<ClientResponseType>;
 }
 
@@ -63,7 +64,6 @@ export default abstract class AbstractClient extends EventEmitter {
   backgroundPlugins: Plugins;
   connection: ClientConnection | null | undefined;
   activePlugins: Set<string>;
-
   device: BaseDevice;
   logger: Logger;
 
@@ -71,6 +71,11 @@ export default abstract class AbstractClient extends EventEmitter {
   private readonly serverAddOnControls: ServerAddOnControls;
   private readonly flipperServer: FlipperServer;
 
+  private resolveInitPromise!: (_: unknown) => void;
+  readonly initializationPromise = new Promise((_resolve) => {
+    this.resolveInitPromise = _resolve;
+  });
+
   constructor(
     id: string,
     query: ClientQuery,
@@ -116,6 +121,7 @@ export default abstract class AbstractClient extends EventEmitter {
       }
     });
     this.emit('plugins-change');
+    this.resolveInitPromise?.(null);
   }
 
   // get the supported plugins