Remove redundant OptionalMethodChannel methods (#81930)

packages/flutter/lib/src/services/platform_channel.dart

@@ -142,6 +142,25 @@ class MethodChannel {
   BinaryMessenger get binaryMessenger => _binaryMessenger ?? ServicesBinding.instance!.defaultBinaryMessenger;
   final BinaryMessenger? _binaryMessenger;
 
+  /// Backend implementation of [invokeMethod].
+  ///
+  /// The `method` and `arguments` arguments are used to create a [MethodCall]
+  /// object that is passed to the [codec]'s [MethodCodec.encodeMethodCall]
+  /// method. The resulting message is then sent to the embedding using the
+  /// [binaryMessenger]'s [BinaryMessenger.send] method.
+  ///
+  /// If the result is null and `missingOk` is true, this returns null. (This is
+  /// the behaviour of [OptionalMethodChannel.invokeMethod].)
+  ///
+  /// If the result is null and `missingOk` is false, this throwsa
+  /// [MissingPluginException]. (This is the behaviour of
+  /// [MethodChannel.invokeMethod].)
+  ///
+  /// Otherwise, the result is decoded using the [codec]'s
+  /// [MethodCodec.decodeEnvelope] method.
+  ///
+  /// The `T` type argument is the expected return type. It is treated as
+  /// nullable.
   @optionalTypeArgs
   Future<T?> _invokeMethod<T>(String method, { required bool missingOk, dynamic arguments }) async {
     assert(method != null);
@@ -333,29 +352,29 @@ class MethodChannel {
 
   /// An implementation of [invokeMethod] that can return typed lists.
   ///
-  /// Dart generics are reified, meaning that an untyped List<dynamic>
-  /// cannot masquerade as a List<T>. Since invokeMethod can only return
-  /// dynamic maps, we instead create a new typed list using [List.cast].
+  /// Dart generics are reified, meaning that an untyped `List<dynamic>` cannot
+  /// masquerade as a `List<T>`. Since [invokeMethod] can only return dynamic
+  /// maps, we instead create a new typed list using [List.cast].
   ///
   /// See also:
   ///
   ///  * [invokeMethod], which this call delegates to.
   Future<List<T>?> invokeListMethod<T>(String method, [ dynamic arguments ]) async {
-    final List<dynamic>? result = await invokeMethod<List<dynamic>?>(method, arguments);
+    final List<dynamic>? result = await invokeMethod<List<dynamic>>(method, arguments);
     return result?.cast<T>();
   }
 
   /// An implementation of [invokeMethod] that can return typed maps.
   ///
-  /// Dart generics are reified, meaning that an untyped Map<dynamic, dynamic>
-  /// cannot masquerade as a Map<K, V>. Since invokeMethod can only return
+  /// Dart generics are reified, meaning that an untyped `Map<dynamic, dynamic>`
+  /// cannot masquerade as a `Map<K, V>`. Since [invokeMethod] can only return
   /// dynamic maps, we instead create a new typed map using [Map.cast].
   ///
   /// See also:
   ///
   ///  * [invokeMethod], which this call delegates to.
   Future<Map<K, V>?> invokeMapMethod<K, V>(String method, [ dynamic arguments ]) async {
-    final Map<dynamic, dynamic>? result = await invokeMethod<Map<dynamic, dynamic>?>(method, arguments);
+    final Map<dynamic, dynamic>? result = await invokeMethod<Map<dynamic, dynamic>>(method, arguments);
     return result?.cast<K, V>();
   }
 
@@ -453,26 +472,13 @@ class MethodChannel {
 /// instead of throwing an exception.
 class OptionalMethodChannel extends MethodChannel {
   /// Creates a [MethodChannel] that ignores missing platform plugins.
-  const OptionalMethodChannel(String name, [MethodCodec codec = const StandardMethodCodec()])
-    : super(name, codec);
+  const OptionalMethodChannel(String name, [MethodCodec codec = const StandardMethodCodec(), BinaryMessenger? binaryMessenger])
+    : super(name, codec, binaryMessenger);
 
   @override
   Future<T?> invokeMethod<T>(String method, [ dynamic arguments ]) async {
     return super._invokeMethod<T>(method, missingOk: true, arguments: arguments);
   }
-
-  @override
-  Future<List<T>?> invokeListMethod<T>(String method, [ dynamic arguments ]) async {
-    final List<dynamic>? result = await invokeMethod<List<dynamic>>(method, arguments);
-    return result?.cast<T>();
-  }
-
-  @override
-  Future<Map<K, V>?> invokeMapMethod<K, V>(String method, [ dynamic arguments ]) async {
-    final Map<dynamic, dynamic>? result = await invokeMethod<Map<dynamic, dynamic>>(method, arguments);
-    return result?.cast<K, V>();
-  }
-
 }
 
 /// A named channel for communicating with platform plugins using event streams.