New Crashlytics Crash Reporting APIs (#1351)

* Changes to package import statements

Without these changes to the package import statements, if a user uncomments the FirebaseCrashlytics code, they will get a bunch of errors.

* Commented out import statements & added instructions

* Update crashlytics.dart

Upgrade Crashlytics.dart to use recently released fatal crash APIs
https://firebase.blog/posts/2022/07/whats-new-in-crashlytics-for-flutter

* Ran dart format on changed files

game_template/lib/src/crashlytics/crashlytics.dart

@@ -40,14 +40,15 @@ Future<void> guardWithCrashlytics(
       crashlytics?.log(message);
 
       if (record.level >= Level.SEVERE) {
-        crashlytics?.recordError(message, filterStackTrace(StackTrace.current));
+        crashlytics?.recordError(message, filterStackTrace(StackTrace.current),
+            fatal: true);
       }
     });
 
     // Pass all uncaught errors from the framework to Crashlytics.
     if (crashlytics != null) {
       WidgetsFlutterBinding.ensureInitialized();
-      FlutterError.onError = crashlytics.recordFlutterError;
+      FlutterError.onError = crashlytics.recordFlutterFatalError;
     }
 
     if (!kIsWeb) {
@@ -56,9 +57,8 @@ Future<void> guardWithCrashlytics(
       Isolate.current.addErrorListener(RawReceivePort((dynamic pair) async {
         final errorAndStacktrace = pair as List<dynamic>;
         await crashlytics?.recordError(
-          errorAndStacktrace.first,
+            errorAndStacktrace.first, errorAndStacktrace.last as StackTrace?,
-          errorAndStacktrace.last as StackTrace?,
+            fatal: true);
-        );
       }).sendPort);
     }
 
@@ -68,7 +68,7 @@ Future<void> guardWithCrashlytics(
     // This sees all errors that occur in the runZonedGuarded zone.
     debugPrint('ERROR: $error\n\n'
         'STACK:$stack');
-    crashlytics?.recordError(error, stack);
+    crashlytics?.recordError(error, stack, fatal: true);
   });
 }