PerformanceModeRequestHandle should dispatch creation and disposal events. (flutter#137642)

Author: ksokolovskyi

packages/flutter/lib/src/scheduler/binding.dart

@@ -196,7 +196,17 @@ typedef _PerformanceModeCleanupCallback = VoidCallback;
 /// To create a [PerformanceModeRequestHandle], use [SchedulerBinding.requestPerformanceMode].
 /// The component that makes the request is responsible for disposing the handle.
 class PerformanceModeRequestHandle {
-  PerformanceModeRequestHandle._(_PerformanceModeCleanupCallback this._cleanup);
+  PerformanceModeRequestHandle._(_PerformanceModeCleanupCallback this._cleanup) {
+    // TODO(polina-c): stop duplicating code across disposables
+    // https://github.com/flutter/flutter/issues/137435
+    if (kFlutterMemoryAllocationsEnabled) {
+      MemoryAllocations.instance.dispatchObjectCreated(
+        library: 'package:flutter/scheduler.dart',
+        className: '$PerformanceModeRequestHandle',
+        object: this,
+      );
+    }
+  }
 
   _PerformanceModeCleanupCallback? _cleanup;
 
@@ -206,6 +216,11 @@ class PerformanceModeRequestHandle {
   /// This method must only be called once per object.
   void dispose() {
     assert(_cleanup != null);
+    // TODO(polina-c): stop duplicating code across disposables
+    // https://github.com/flutter/flutter/issues/137435
+    if (kFlutterMemoryAllocationsEnabled) {
+      MemoryAllocations.instance.dispatchObjectDisposed(object: this);
+    }
     _cleanup!();
     _cleanup = null;
   }

packages/flutter/test/scheduler/performance_mode_test.dart

@@ -7,6 +7,7 @@ import 'dart:ui';
 import 'package:flutter/scheduler.dart';
 import 'package:flutter/widgets.dart';
 import 'package:flutter_test/flutter_test.dart';
+import 'package:leak_tracker_flutter_testing/leak_tracker_flutter_testing.dart';
 
 void main() {
   late SchedulerBinding binding;
@@ -53,4 +54,14 @@ void main() {
     requestHandle2?.dispose();
     expect(binding.debugGetRequestedPerformanceMode(), isNull);
   });
+
+  test('PerformanceModeRequestHandle dispatches memory events', () async {
+    await expectLater(
+      await memoryEvents(
+        () => binding.requestPerformanceMode(DartPerformanceMode.latency)!.dispose(),
+        PerformanceModeRequestHandle,
+      ),
+      areCreateAndDispose,
+    );
+  });
 }