Improve based on Fei's comments/feedbacks

- Updated  dependencies versions
- Remove redundant namespace declarations

Author: zwu52

packages-exp/messaging-compat/package.json

@@ -31,18 +31,17 @@
   },
   "dependencies": {
     "@firebase/messaging-exp": "0.0.900",
-    "@firebase/component": "0.2.0",
+    "@firebase/component": "0.2.1",
     "@firebase/installations-exp": "0.0.900",
-    "@firebase/util": "0.3.4",
-    "idb": "3.0.2",
-    "tslib": "^1.11.1"
+    "@firebase/util": "0.4.0",
+    "tslib": "^2.0.0"
   },
   "devDependencies": {
     "@firebase/app-compat": "0.0.900",
     "@rollup/plugin-json": "4.1.0",
     "rollup-plugin-typescript2": "0.29.0",
     "ts-essentials": "7.0.1",
-    "typescript": "4.0.5"
+    "typescript": "4.2.2"
   },
   "repository": {
     "directory": "packages/messaging",

packages-exp/messaging-compat/src/messaging-compat.ts

@@ -31,9 +31,6 @@ import { NextFn, Observer, Unsubscribe } from '@firebase/util';
 import { onBackgroundMessage } from '@firebase/messaging-exp/sw';
 
 export class MessagingCompat implements _FirebaseService {
-  readonly app!: AppCompat;
-  readonly messaging!: FirebaseMessaging;
-
   swRegistration?: ServiceWorkerRegistration;
   vapidKey?: string;
 
@@ -47,7 +44,7 @@ export class MessagingCompat implements _FirebaseService {
     | Observer<MessagePayload>
     | null = null;
 
-  constructor(app: AppCompat, messaging: FirebaseMessaging) {
+  constructor(readonly app: AppCompat, readonly messaging: FirebaseMessaging) {
     this.app = app;
     this.messaging = messaging;
   }

packages-exp/messaging-compat/src/registerMessagingCompat.ts

@@ -22,16 +22,12 @@ import {
   InstanceFactory
 } from '@firebase/component';
 
-import { FirebaseApp } from '@firebase/app-compat';
-import { FirebaseMessaging } from '@firebase/messaging-exp';
 import { MessagingCompat } from './messaging-compat';
 import { _registerComponent } from '@firebase/app-exp';
 
 declare module '@firebase/component' {
   interface NameServiceMapping {
-    'app-compat': FirebaseApp;
     'messaging-compat': MessagingCompat;
-    'messaging-exp': FirebaseMessaging;
   }
 }