title: Initializing FIrebase on Flutter throws error
body: <p>So I have been trying to initialize my firebase with my flutter app but it keeps throwing an error every time, the code has no problem since flutter builds the app fine but just not firebase.
  So this is my code to initialize firebase;</p>
  <pre><code>import 'package:flutter/material.dart';
  import 'package:firebase_core/firebase_core.dart';
  
  void main() async {
    WidgetsFlutterBinding.ensureInitialized();
    await Firebase.initializeApp();
    runApp(const MyApp());
  }
  
  class MyApp extends StatefulWidget {
    const MyApp({Key? key}) : super(key: key);
  
    @override
    _MyAppState createState() =&gt; _MyAppState();
  }
  
  class _MyAppState extends State&lt;MyApp&gt; {
    bool _initialized = false;
    bool _error = false;
  
    void initializeFlutterFire() async {
      try {
        // Wait for Firebase to initialize and set `_initialized` state to true
        await Firebase.initializeApp();
        setState(() {
          _initialized = true;
        });
      } catch (e) {
        // Set `_error` state to true if Firebase initialization fails
        setState(() {
          _error = true;
        });
      }
    }
  
    @override
    void initState() {
      initializeFlutterFire();
      super.initState();
    }
    @override
    Widget build(BuildContext context) {
      return MaterialApp();
  </code></pre>
  <p>and this is the error I keep getting:</p>
  <pre><code>Error: Assertion failed:
  file:///home/pete/snap/flutter/common/flutter/.pub-cache/hosted/pub.dartlang.org/firebase_core_web-1.4.0/lib/src/fire
  base_core_web.dart:271:11
  options != null
  &quot;FirebaseOptions cannot be null when creating the default app.&quot;
      at Object.throw_ [as throw] (http://localhost:35305/dart_sdk.js:5061:11)
      at Object.assertFailed (http://localhost:35305/dart_sdk.js:4986:15)
      at firebase_core_web.FirebaseCoreWeb.new.initializeApp
      (http://localhost:35305/packages/firebase_core_web/firebase_core_web.dart.lib.js:243:42)
      at initializeApp.next (&lt;anonymous&gt;)
      at http://localhost:35305/dart_sdk.js:38640:33
      at _RootZone.runUnary (http://localhost:35305/dart_sdk.js:38511:59)
      at _FutureListener.thenAwait.handleValue (http://localhost:35305/dart_sdk.js:33713:29)
      at handleValueCallback (http://localhost:35305/dart_sdk.js:34265:49)
      at Function._propagateToListeners (http://localhost:35305/dart_sdk.js:34303:17)
      at _Future.new.[_completeWithValue] (http://localhost:35305/dart_sdk.js:34151:23)
      at async._AsyncCallbackEntry.new.callback (http://localhost:35305/dart_sdk.js:34172:35)
      at Object._microtaskLoop (http://localhost:35305/dart_sdk.js:38778:13)
      at _startMicrotaskLoop (http://localhost:35305/dart_sdk.js:38784:13)
      at http://localhost:35305/dart_sdk.js:34519:9
  </code></pre>