DraggableScrollableActuator should dispose notifier. (#133917)

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

@@ -1015,12 +1015,12 @@ class _DraggableScrollableSheetScrollPosition extends ScrollPositionWithSingleCo
 /// in library users' code). Generally, it's easier to control the sheet
 /// directly by creating a controller and passing the controller to the sheet in
 /// its constructor (see [DraggableScrollableSheet.controller]).
-class DraggableScrollableActuator extends StatelessWidget {
+class DraggableScrollableActuator extends StatefulWidget {
   /// Creates a widget that can notify descendent [DraggableScrollableSheet]s
   /// to reset to their initial position.
   ///
   /// The [child] parameter is required.
-  DraggableScrollableActuator({
+  const DraggableScrollableActuator({
     super.key,
     required this.child,
   });
@@ -1031,7 +1031,6 @@ class DraggableScrollableActuator extends StatelessWidget {
   /// Must not be null.
   final Widget child;
 
-  final _ResetNotifier _notifier = _ResetNotifier();
 
   /// Notifies any descendant [DraggableScrollableSheet] that it should reset
   /// to its initial position.
@@ -1047,9 +1046,22 @@ class DraggableScrollableActuator extends StatelessWidget {
     return notifier._sendReset();
   }
 
+  @override
+  State<DraggableScrollableActuator> createState() => _DraggableScrollableActuatorState();
+}
+
+class _DraggableScrollableActuatorState extends State<DraggableScrollableActuator> {
+  final _ResetNotifier _notifier = _ResetNotifier();
+
   @override
   Widget build(BuildContext context) {
-    return _InheritedResetNotifier(notifier: _notifier, child: child);
+    return _InheritedResetNotifier(notifier: _notifier, child: widget.child);
+  }
+
+  @override
+  void dispose() {
+    _notifier.dispose();
+    super.dispose();
   }
 }
 

packages/flutter/test/material/floating_action_button_location_test.dart

@@ -415,7 +415,7 @@ void main() {
       expect(tester.getCenter(find.byType(FloatingActionButton)), const Offset(_leftOffsetX, _floatOffsetY));
     });
 
-    testWidgets('centerFloat', (WidgetTester tester) async {
+    testWidgetsWithLeakTracking('centerFloat', (WidgetTester tester) async {
       await tester.pumpWidget(_singleFabScaffold(FloatingActionButtonLocation.centerFloat));
 
       expect(tester.getCenter(find.byType(FloatingActionButton)), const Offset(_centerOffsetX, _floatOffsetY));
@@ -1037,7 +1037,7 @@ void main() {
       );
     });
 
-    testWidgets('centerFloat', (WidgetTester tester) async {
+    testWidgetsWithLeakTracking('centerFloat', (WidgetTester tester) async {
       const Rect defaultRect = Rect.fromLTRB(372.0, 478.0, 428.0, 534.0);
       // Positioned relative to BottomNavigationBar
       const Rect bottomNavigationBarRect = Rect.fromLTRB(372.0, 422.0, 428.0, 478.0);