[firebase_messaging] fix crash when func deleteInstanceID return result in incorrect thread (flutter-team-archive#1756)

* [firebase_messaging] fix crash when calling func deleteInstanceID (flutter-team-archive#1756)

Author: wildtigon

packages/firebase_messaging/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 5.0.5
+
+* On Android, fix crash when calling `deleteInstanceID` with latest Flutter engine.
+
 ## 5.0.4
 
 * Automatically use version from pubspec.yaml when reporting usage to Firebase.

packages/firebase_messaging/android/src/main/java/io/flutter/plugins/firebasemessaging/FirebaseMessagingPlugin.java

@@ -148,10 +148,30 @@ public void onComplete(@NonNull Task<InstanceIdResult> task) {
                 public void run() {
                   try {
                     FirebaseInstanceId.getInstance().deleteInstanceId();
-                    result.success(true);
+                    if (registrar.activity() != null) {
+                      registrar
+                          .activity()
+                          .runOnUiThread(
+                              new Runnable() {
+                                @Override
+                                public void run() {
+                                  result.success(true);
+                                }
+                              });
+                    }
                   } catch (IOException ex) {
                     Log.e(TAG, "deleteInstanceID, error:", ex);
-                    result.success(false);
+                    if (registrar.activity() != null) {
+                      registrar
+                          .activity()
+                          .runOnUiThread(
+                              new Runnable() {
+                                @Override
+                                public void run() {
+                                  result.success(false);
+                                }
+                              });
+                    }
                   }
                 }
               })

packages/firebase_messaging/pubspec.yaml

@@ -3,7 +3,7 @@ description: Flutter plugin for Firebase Cloud Messaging, a cross-platform
   messaging solution that lets you reliably deliver messages on Android and iOS.
 author: Flutter Team <flutter-dev@googlegroups.com>
 homepage: https://github.com/flutter/plugins/tree/master/packages/firebase_messaging
-version: 5.0.4
+version: 5.0.5
 
 flutter:
   plugin: