Fixing memory leak in EditableTextState (#131377)

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

@@ -2125,6 +2125,7 @@ class EditableTextState extends State<EditableText> with AutomaticKeepAliveClien
   late final Simulation _iosBlinkCursorSimulation = _DiscreteKeyFrameSimulation.iOSBlinkingCaret();
 
   final ValueNotifier<bool> _cursorVisibilityNotifier = ValueNotifier<bool>(true);
+  late final ValueNotifier<bool> _debugCursorNotifier;
   final GlobalKey _editableKey = GlobalKey();
 
   /// Detects whether the clipboard can paste.
@@ -2789,6 +2790,7 @@ class EditableTextState extends State<EditableText> with AutomaticKeepAliveClien
     _scrollController.addListener(_onEditableScroll);
     _cursorVisibilityNotifier.value = widget.showCursor;
     _spellCheckConfiguration = _inferSpellCheckConfiguration(widget.spellCheckConfiguration);
+    _debugCursorNotifier = ValueNotifier<bool>(widget.showCursor);
   }
 
   // Whether `TickerMode.of(context)` is true and animations (like blinking the
@@ -2933,6 +2935,7 @@ class EditableTextState extends State<EditableText> with AutomaticKeepAliveClien
 
   @override
   void dispose() {
+    _debugCursorNotifier.dispose();
     _internalScrollController?.dispose();
     _currentAutofillScope?.unregister(autofillId);
     widget.controller.removeListener(_didChangeTextEditingValue);
@@ -4853,7 +4856,7 @@ class EditableTextState extends State<EditableText> with AutomaticKeepAliveClien
                             cursorColor: _cursorColor,
                             backgroundCursorColor: widget.backgroundCursorColor,
                             showCursor: EditableText.debugDeterministicCursor
-                                ? ValueNotifier<bool>(widget.showCursor)
+                                ? _debugCursorNotifier
                                 : _cursorVisibilityNotifier,
                             forceLine: widget.forceLine,
                             readOnly: widget.readOnly,

packages/flutter/test/material/text_selection_theme_test.dart

@@ -167,18 +167,7 @@ void main() {
     await tester.pumpAndSettle();
     final RenderBox handle = tester.firstRenderObject<RenderBox>(find.byType(CustomPaint));
     expect(handle, paints..path(color: defaultSelectionHandleColor));
-  },
-    // TODO(polina-c): remove after fixing
-    // https://github.com/flutter/flutter/issues/130469
-    leakTrackingTestConfig: const LeakTrackingTestConfig(
-      notDisposedAllowList: <String, int?>{
-        'ValueNotifier<MagnifierInfo>': 1,
-        'ValueNotifier<_OverlayEntryWidgetState?>': 2,
-        'ValueNotifier<bool>': 2,
-        '_InputBorderGap': 1,
-      },
-    ),
-  );
+  });
 
   testWidgets('ThemeData.textSelectionTheme will be used if provided', (WidgetTester tester) async {
     const TextSelectionThemeData textSelectionTheme = TextSelectionThemeData(