title: Flutter notification is blank when app is in background
body: <p>When app is in background, onResume is not called but I get some kind of default notification in tray with blank icon and no image. </p>
  
  <p>When I click this notification, onResume is then called and app is opened but does not navigate to the correct route.</p>
  
  <p>Firebase message is behaving as expected when flutter app is in foreground.
  - onMessage is called and notification has icon and image in tray.</p>
  
  <p>I'm wondering if the setup for notification/messaging is in the wrong location.</p>
  
  <pre><code>  class NotificationIcon extends StatefulWidget {
    @override
    NotificationIconState createState() =&gt; NotificationIconState();
  }
  
  class NotificationIconState extends State&lt;NotificationIcon&gt; {
    FirebaseMessaging firebaseMessaging = new FirebaseMessaging();
  
    void fcmSubscribe() {
      ...
    }
  
    void fcmUnSubscribe() {
     ...
    }
  
    Future showBigPictureNotification(Map&lt;String, dynamic&gt; message) async {
      ...
      var bigPictureStyleInformation = new BigPictureStyleInformation(
          bigPicturePath, BitmapSource.FilePath,
          contentTitle: title, summaryText: messageText);
      var androidPlatformChannelSpecifics = new AndroidNotificationDetails(
          '', topic, messageText,
          style: AndroidNotificationStyle.BigPicture,
          styleInformation: bigPictureStyleInformation);
      var platformChannelSpecifics =
          new NotificationDetails(androidPlatformChannelSpecifics, null);
      await flutterLocalNotificationsPlugin.show(
          0, title, messageText, platformChannelSpecifics);
    }
  
    @override
    void initState() {
      super.initState();
      firebaseMessaging.configure(
        onMessage: (Map&lt;String, dynamic&gt; message) async {
          print("onMessage: $message");
          currentMessage = message;
          await showBigPictureNotification(currentMessage);
        },
        onLaunch: (Map&lt;String, dynamic&gt; message) async {
          print("onLaunch: $message");
          currentMessage = message;
          await showBigPictureNotification(currentMessage);
        },
        onResume: (Map&lt;String, dynamic&gt; message) async {
          print("onResume: $message");
          currentMessage = message;
          await showBigPictureNotification(currentMessage);
        },
      );
  
      onSelectNotification(String payload) async {
        await navigatorKey.currentState.push(new MaterialPageRoute(...));
      }
  
      firebaseMessaging.requestNotificationPermissions();
      flutterLocalNotificationsPlugin = new FlutterLocalNotificationsPlugin();
      var initializationSettingsAndroid =
          new AndroidInitializationSettings('ic_stat_fiber_new');
      var initializationSettings =
          new InitializationSettings(initializationSettingsAndroid, null);
      flutterLocalNotificationsPlugin.initialize(initializationSettings,
          onSelectNotification: onSelectNotification);
    }
  
    @override
    Widget build(BuildContext context) {
      &lt; widget &gt;
    }
  }
  
  </code></pre>
  
  <pre><code>flutter doctor -v
  [√] Flutter (Channel stable, v1.2.1, on Microsoft Windows [Version 10.0.16299.1004], locale en-IE)
      • Flutter version 1.2.1 at flutter
      • Framework revision 8661d8aecd (8 weeks ago), 2019-02-14 19:19:53 -0800
      • Engine revision 3757390fa4
      • Dart version 2.1.2 (build 2.1.2-dev.0.0 0a7dcf17eb)
  
  [√] Android toolchain - develop for Android devices (Android SDK version 28.0.3)
      • Android SDK at AppData\Local\Android\sdk
      • Android NDK location not configured (optional; useful for native profiling support)
      • Platform android-28, build-tools 28.0.3
      • Java binary at: C:\Program Files\Android\Android Studio\jre\bin\java
      • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-1136-b06)
      • All Android licenses accepted.
  
  [√] Android Studio (version 3.2)
      • Android Studio at C:\Program Files\Android\Android Studio
      • Flutter plugin version 31.1.1
      • Dart plugin version 181.5656
      • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-1136-b06)
  
  [√] VS Code (version 1.32.3)
      • VS Code at \AppData\Local\Programs\Microsoft VS Code
      • Flutter extension version 2.24.0
  
  [√] Connected device (1 available)
      • Android SDK built for x86 • emulator-5554 • android-x86 • Android 9 (API 28) (emulator)
  
  • No issues found!
  </code></pre>
  
  <pre><code>dependencies:
    flutter:
      sdk: flutter
    http:
    url_launcher: 4.2.0+3
    flutter_image: ^1.0.0
    path_provider: 0.4.1
    flutter_downloader: 1.1.3
    fluttertoast: ^2.2.11
    pin_code_view: 0.1.0
    image_picker: 0.4.12+1
    firebase_core: 0.2.5+1
    firebase_storage: 1.1.0+1
    uuid: ^1.0.0
    cupertino_icons: ^0.1.0
    permission_handler: 1.0.1
    transparent_image: 0.1.0
    shared_preferences: 0.4.3
    flutter_launcher_icons: ^0.7.0
    firebase_messaging: 2.1.0
    flutter_local_notifications: 0.4.5
  </code></pre>
  
  <p>On older versions of some dependencies due to AndroidX issue.</p>
  
  <p>Working Notification when app in foreground
  <a href="https://i.stack.imgur.com/jdkUT.png" rel="noreferrer">working_notificaiton</a></p>
  
  <p>Not working Notification when app in foreground
  <a href="https://i.stack.imgur.com/i1UAK.png" rel="noreferrer">not_working_notification</a></p>