Remove the extra wrapping of `Listener` (#67340)

packages/flutter/lib/src/widgets/basic.dart

@@ -5804,7 +5804,7 @@ class WidgetToRenderBoxAdapter extends LeafRenderObjectWidget {
 /// }
 /// ```
 /// {@end-tool}
-class Listener extends StatelessWidget {
+class Listener extends SingleChildRenderObjectWidget {
   /// Creates a widget that forwards point events to callbacks.
   ///
   /// The [behavior] argument defaults to [HitTestBehavior.deferToChild].
@@ -5819,8 +5819,7 @@ class Listener extends StatelessWidget {
     this.behavior = HitTestBehavior.deferToChild,
     Widget? child,
   }) : assert(behavior != null),
-       _child = child,
-       super(key: key);
+       super(key: key, child: child);
 
   /// Called when a pointer comes into contact with the screen (for touch
   /// pointers), or has its button pressed (for mouse pointers) at this widget's
@@ -5856,52 +5855,6 @@ class Listener extends StatelessWidget {
   /// How to behave during hit testing.
   final HitTestBehavior behavior;
 
-  // The widget listened to by the listener.
-  //
-  // The reason why we don't expose it is that once the deprecated methods are
-  // removed, Listener will no longer need to store the child, but will pass
-  // the child to `super` instead.
-  final Widget? _child;
-
-  @override
-  Widget build(BuildContext context) {
-    // TODO(dkwingsmt): Remove the extra wrapper, and make `Listener` a
-    // StatelessWidget. https://github.com/flutter/flutter/issues/65586
-    return _PointerListener(
-      onPointerDown: onPointerDown,
-      onPointerUp: onPointerUp,
-      onPointerMove: onPointerMove,
-      onPointerHover: onPointerHover,
-      onPointerCancel: onPointerCancel,
-      onPointerSignal: onPointerSignal,
-      behavior: behavior,
-      child: _child,
-    );
-  }
-}
-
-class _PointerListener extends SingleChildRenderObjectWidget {
-  const _PointerListener({
-    Key? key,
-    this.onPointerDown,
-    this.onPointerMove,
-    this.onPointerUp,
-    this.onPointerHover,
-    this.onPointerCancel,
-    this.onPointerSignal,
-    this.behavior = HitTestBehavior.deferToChild,
-    Widget? child,
-  }) : assert(behavior != null),
-       super(key: key, child: child);
-
-  final PointerDownEventListener? onPointerDown;
-  final PointerMoveEventListener? onPointerMove;
-  final PointerUpEventListener? onPointerUp;
-  final PointerHoverEventListener? onPointerHover;
-  final PointerCancelEventListener? onPointerCancel;
-  final PointerSignalEventListener? onPointerSignal;
-  final HitTestBehavior behavior;
-
   @override
   RenderPointerListener createRenderObject(BuildContext context) {
     return RenderPointerListener(

packages/flutter/test/material/debug_test.dart

@@ -157,7 +157,6 @@ void main() {
       '     Semantics\n'
       '     FocusScope\n'
       '     AbsorbPointer\n'
-      '     _PointerListener\n'
       '     Listener\n'
       '     HeroControllerScope\n'
       '     Navigator-[GlobalObjectKey<NavigatorState> _WidgetsAppState#00000]\n'