addressed deprecation warnings

analysis_options.yaml

@@ -28,10 +28,6 @@ analyzer:
  missing_return: warning
  # allow having TODOs in the code
  todo: ignore
- # Ignore analyzer hints for updating pubspecs when using Future or
- # Stream and not importing dart:async
- # Please see https://github.com/flutter/flutter/pull/24528 for details.
- sdk_version_async_exported_from_core: ignore
  exclude:
  - "bin/cache/**"
  # the following two are relative to the stocks example and the flutter package respectively
@@ -99,12 +95,11 @@ linter:
  - hash_and_equals
  - implementation_imports
  # - invariant_booleans # too many false positives: https://github.com/dart-lang/linter/issues/811
- - iterable_contains_unrelated_type
  # - join_return_with_assignment # not yet tested
  - library_names
  - library_prefixes
  - lines_longer_than_80_chars
- - list_remove_unrelated_type
+ - collection_methods_unrelated_type
  # - literal_only_boolean_expressions # too many false positives: https://github.com/dart-lang/sdk/issues/34181
  - no_adjacent_strings_in_list
  - no_duplicate_case_values

flutter_appauth_platform_interface/test/method_channel_flutter_appauth_test.dart

@@ -8,8 +8,10 @@ void main() {
  const MethodChannel channel =
  MethodChannel('crossingthestreams.io/flutter_appauth');
  final List<MethodCall> log = <MethodCall>[];
- channel.setMockMethodCallHandler((MethodCall methodCall) async {
+ TestDefaultBinaryMessengerBinding.instance.defaultBinaryMessenger
+ .setMockMethodCallHandler(channel, (MethodCall methodCall) async {
  log.add(methodCall);
+ return null;
  });
 
  tearDown(() {