fix: Call codec.dispose in tests of engine/src/flutter (#161115)

PR derived from https://github.com/flutter/flutter/pull/159945.

Added `codec.dispose()` for directories under `engine/src/flutter`.

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [x] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [x] I read and followed the [Flutter Style Guide], including [Features
we expect every widget to implement].
- [x] I signed the [CLA].
- [ ] I listed at least one issue that this PR fixes in the description
above.
- [ ] I updated/added relevant documentation (doc comments with `///`).
- [x] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [x] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
- [x] All existing and new tests are passing.

If you need help, consider asking for advice on the #hackers-new channel
on [Discord].

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[Contributor Guide]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#overview
[Tree Hygiene]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md
[test-exempt]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#tests
[Flutter Style Guide]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Style-guide-for-Flutter-repo.md
[Features we expect every widget to implement]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Style-guide-for-Flutter-repo.md#features-we-expect-every-widget-to-implement
[CLA]: https://cla.developers.google.com/
[flutter/tests]: https://github.com/flutter/tests
[breaking change policy]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#handling-breaking-changes
[Discord]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Chat.md
[Data Driven Fixes]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Data-driven-Fixes.md

engine/src/flutter/lib/web_ui/test/canvaskit/image_golden_test.dart

@@ -14,8 +14,6 @@ import 'package:ui/ui.dart' as ui;
 import 'common.dart';
 import 'test_data.dart';
 
-List<TestCodec>? testCodecs;
-
 void main() {
   internalBootstrapBrowserTest(() => testMain);
 }
@@ -29,6 +27,11 @@ abstract class TestCodec {
   Future<ui.Codec> getCodec() async => _cachedCodec ??= await createCodec();
 
   Future<ui.Codec> createCodec();
+
+  void dispose() {
+    _cachedCodec?.dispose();
+    _cachedCodec = null;
+  }
 }
 
 abstract class TestFileCodec extends TestCodec {
@@ -134,13 +137,10 @@ class BitmapSingleFrameCodec implements ui.Codec {
 }
 
 Future<void> testMain() async {
-  Future<List<TestCodec>> createTestCodecs({
+  final HttpFetchResponse listingResponse = await httpFetch('/test_images/');
-    int testTargetWidth = 300,
+  final List<String> testFiles = (await listingResponse.json() as List<dynamic>).cast<String>();
-    int testTargetHeight = 300,
-  }) async {
-    final HttpFetchResponse listingResponse = await httpFetch('/test_images/');
-    final List<String> testFiles = (await listingResponse.json() as List<dynamic>).cast<String>();
 
+  List<TestCodec> createTestCodecs({int testTargetWidth = 300, int testTargetHeight = 300}) {
     // Sanity-check the test file list. If suddenly test files are moved or
     // deleted, and the test server returns an empty list, or is missing some
     // important test files, we want to know.
@@ -192,8 +192,6 @@ Future<void> testMain() async {
     return testCodecs;
   }
 
-  testCodecs = await createTestCodecs();
-
   group('CanvasKit Images', () {
     setUpCanvasKitTest(withImplicitView: true);
 
@@ -202,7 +200,8 @@ Future<void> testMain() async {
     });
 
     group('Codecs', () {
-      for (final TestCodec testCodec in testCodecs!) {
+      final List<TestCodec> testCodecs = createTestCodecs();
+      for (final TestCodec testCodec in testCodecs) {
         test('${testCodec.description} can create an image', () async {
           try {
             final ui.Codec codec = await testCodec.getCodec();
@@ -247,6 +246,9 @@ Future<void> testMain() async {
           );
         });
       }
+      for (final testCodec in testCodecs) {
+        testCodec.dispose();
+      }
     });
 
     test('crossOrigin requests cause an error', () async {

engine/src/flutter/lib/web_ui/test/html/drawing/canvas_draw_image_golden_test.dart

@@ -39,6 +39,7 @@ Future<void> testMain() async {
       final Uint8List imageData = base64Decode(base64PngData);
       final Codec codec = await instantiateImageCodec(imageData);
       final FrameInfo frameInfo = await codec.getNextFrame();
+      codec.dispose();
 
       const Rect bounds = Rect.fromLTRB(0, 0, 400, 300);
       final EnginePictureRecorder recorder = EnginePictureRecorder();

engine/src/flutter/lib/web_ui/test/ui/filters_test.dart

@@ -30,6 +30,7 @@ Future<void> testMain() async {
     expect(codec.frameCount, 1);
 
     final ui.FrameInfo info = await codec.getNextFrame();
+    codec.dispose();
     final ui.Image image = info.image;
     expect(image.width, 128);
     expect(image.height, 128);

engine/src/flutter/lib/web_ui/test/ui/image_golden_test.dart

@@ -381,6 +381,7 @@ Future<void> testMain() async {
     expect(codec.frameCount, 1);
 
     final ui.FrameInfo info = await codec.getNextFrame();
+    codec.dispose();
     return info.image;
   });
 
@@ -393,6 +394,7 @@ Future<void> testMain() async {
     expect(codec.frameCount, 1);
 
     final ui.FrameInfo info = await codec.getNextFrame();
+    codec.dispose();
     expect(info.image.width, 3024);
     expect(info.image.height, 4032);
   });
@@ -424,6 +426,7 @@ Future<void> testMain() async {
       await completer.future;
 
       final DomImageBitmap bitmap = await createImageBitmap(image as JSObject);
+      domWindow.URL.revokeObjectURL(url);
 
       expect(bitmap.width.toDartInt, 150);
       expect(bitmap.height.toDartInt, 150);
@@ -471,6 +474,7 @@ Future<void> testMain() async {
         height: 150,
         transferOwnership: false,
       );
+      domWindow.URL.revokeObjectURL(url);
       return uiImage;
     });
   }
@@ -485,6 +489,7 @@ Future<void> testMain() async {
     expect(codec.frameCount, 1);
 
     final ui.FrameInfo info = await codec.getNextFrame();
+    codec.dispose();
     return info.image;
   });
 }

engine/src/flutter/testing/dart/codec_test.dart

@@ -49,6 +49,8 @@ void main() {
       } else {
         expect(e.toString(), contains('Codec failed'));
       }
+    } finally {
+      codec.dispose();
     }
   });
 
@@ -64,6 +66,7 @@ void main() {
         frameInfo.image.height,
       ]);
     }
+    codec.dispose();
     expect(
       decodedFrameInfos,
       equals(<List<int>>[
@@ -88,6 +91,7 @@ void main() {
         frameInfo.image.height,
       ]);
     }
+    codec.dispose();
     expect(
       decodedFrameInfos,
       equals(<List<int>>[
@@ -115,6 +119,7 @@ void main() {
         frameInfo.image.height,
       ]);
     }
+    codec.dispose();
     expect(
       decodedFrameInfos,
       equals(<List<int>>[
@@ -136,6 +141,7 @@ void main() {
     } on Exception catch (e) {
       expect(e.toString(), contains('Decoded image has been disposed'));
     }
+    codec.dispose();
   });
 
   test('Animated gif can reuse across multiple frames', () async {
@@ -153,6 +159,7 @@ void main() {
     for (int i = 0; i < 4; i++) {
       frameInfo = await codec.getNextFrame();
     }
+    codec.dispose();
 
     final ui.Image image = frameInfo.image;
     final ByteData imageData = (await image.toByteData(format: ui.ImageByteFormat.png))!;
@@ -180,6 +187,7 @@ void main() {
     for (int i = 0; i < 69; i++) {
       frameInfo = await codec.getNextFrame();
     }
+    codec.dispose();
 
     final ui.Image image = frameInfo.image;
     final ByteData imageData = (await image.toByteData(format: ui.ImageByteFormat.png))!;
@@ -220,6 +228,7 @@ void main() {
         expect(imageData.buffer.asUint8List(), goldenData);
       }
     }
+    codec.dispose();
   });
 
   test('Animated apng alpha type handling', () async {
@@ -237,6 +246,7 @@ void main() {
     image = (await codec.getNextFrame()).image;
     imageData = (await image.toByteData())!;
     expect(imageData.getUint32(0), 0x99000099);
+    codec.dispose();
   });
 
   test('Animated apng background color restore', () async {
@@ -261,6 +271,7 @@ void main() {
     image = (await codec.getNextFrame()).image;
     imageData = (await image.toByteData())!;
     expect(imageData.getUint32(imageData.lengthInBytes - 4), 0x00000000);
+    codec.dispose();
   });
 
   test('Animated apng frame decode does not crash with invalid destination region', () async {
@@ -277,6 +288,8 @@ void main() {
       } else {
         expect(e.toString(), contains('Codec failed'));
       }
+    } finally {
+      codec.dispose();
     }
   });
 
@@ -298,6 +311,8 @@ void main() {
         } else {
           expect(e.toString(), contains('Codec failed'));
         }
+      } finally {
+        codec.dispose();
       }
     },
   );

engine/src/flutter/testing/dart/fragment_shader_test.dart

@@ -544,6 +544,7 @@ Future<Image> _createBlueGreenImage() async {
   );
   final Codec codec = await descriptor.instantiateCodec();
   final FrameInfo frame = await codec.getNextFrame();
+  codec.dispose();
   return frame.image;
 }
 

engine/src/flutter/testing/dart/image_descriptor_test.dart

@@ -22,6 +22,7 @@ void main() {
 
     final Codec codec = await descriptor.instantiateCodec();
     expect(codec.frameCount, 1);
+    codec.dispose();
   });
 
   test('basic image descriptor - encoded - square', () async {
@@ -35,6 +36,7 @@ void main() {
 
     final Codec codec = await descriptor.instantiateCodec();
     expect(codec.frameCount, 1);
+    codec.dispose();
   });
 
   test('basic image descriptor - encoded - animated', () async {
@@ -49,6 +51,7 @@ void main() {
     final Codec codec = await descriptor.instantiateCodec();
     expect(codec.frameCount, 4);
     expect(codec.repetitionCount, -1);
+    codec.dispose();
   });
 
   test('basic image descriptor - raw', () async {
@@ -68,6 +71,7 @@ void main() {
 
     final Codec codec = await descriptor.instantiateCodec();
     expect(codec.frameCount, 1);
+    codec.dispose();
   });
 
   test('HEIC image', () async {
@@ -81,6 +85,7 @@ void main() {
 
     final Codec codec = await descriptor.instantiateCodec();
     expect(codec.frameCount, 1);
+    codec.dispose();
   }, skip: !(Platform.isAndroid || Platform.isIOS || Platform.isMacOS || Platform.isWindows));
 }
 

engine/src/flutter/testing/dart/image_dispose_test.dart

@@ -14,6 +14,7 @@ void main() {
     final Uint8List bytes = await _readFile('2x2.png');
     final Codec codec = await instantiateImageCodec(bytes);
     final FrameInfo frame = await codec.getNextFrame();
+    codec.dispose();
 
     expect(frame.image.width, 2);
     expect(frame.image.height, 2);
@@ -33,6 +34,7 @@ void main() {
     final Uint8List bytes = await _readFile('2x2.png');
     final Codec codec = await instantiateImageCodec(bytes);
     final FrameInfo frame = await codec.getNextFrame();
+    codec.dispose();
 
     expect(frame.image.width, 2);
     expect(frame.image.height, 2);
@@ -71,6 +73,7 @@ void main() {
     final Uint8List bytes = await _readFile('2x2.png');
     final Codec codec = await instantiateImageCodec(bytes);
     final FrameInfo frame = await codec.getNextFrame();
+    codec.dispose();
 
     final Image handle1 = frame.image.clone();
     final Image handle2 = handle1.clone();
@@ -97,6 +100,7 @@ void main() {
     final Uint8List bytes = await _readFile('2x2.png');
     final Codec codec = await instantiateImageCodec(bytes);
     final FrameInfo frame = await codec.getNextFrame();
+    codec.dispose();
 
     final Image handle1 = frame.image.clone();
     final Image handle2 = handle1.clone();
@@ -112,6 +116,7 @@ void main() {
 
     final Codec codec2 = await instantiateImageCodec(bytes);
     final FrameInfo frame2 = await codec2.getNextFrame();
+    codec2.dispose();
 
     expect(frame2.image.isCloneOf(frame.image), false);
   });
@@ -120,6 +125,7 @@ void main() {
     final Uint8List bytes = await _readFile('2x2.png');
     final Codec codec = await instantiateImageCodec(bytes);
     final FrameInfo frame = await codec.getNextFrame();
+    codec.dispose();
 
     expect(frame.image.debugDisposed, false);
 

engine/src/flutter/testing/dart/image_resize_test.dart

@@ -15,6 +15,7 @@ void main() {
     final Uint8List bytes = await readFile('2x2.png');
     final Codec codec = await instantiateImageCodec(bytes);
     final FrameInfo frame = await codec.getNextFrame();
+    codec.dispose();
     final int codecHeight = frame.image.height;
     final int codecWidth = frame.image.width;
     expect(codecHeight, 2);
@@ -25,6 +26,7 @@ void main() {
     final Uint8List bytes = await readFile('2x2.png');
     final Codec codec = await instantiateImageCodec(bytes, targetHeight: 1);
     final FrameInfo frame = await codec.getNextFrame();
+    codec.dispose();
     final int codecHeight = frame.image.height;
     final int codecWidth = frame.image.width;
     expect(codecHeight, 1);
@@ -35,6 +37,7 @@ void main() {
     final Uint8List bytes = await readFile('2x2.png');
     final Codec codec = await instantiateImageCodec(bytes, targetWidth: 1);
     final FrameInfo frame = await codec.getNextFrame();
+    codec.dispose();
     final int codecHeight = frame.image.height;
     final int codecWidth = frame.image.width;
     expect(codecHeight, 1);
@@ -45,6 +48,7 @@ void main() {
     final Uint8List bytes = await readFile('2x2.png');
     final Codec codec = await instantiateImageCodec(bytes, targetWidth: 10);
     final FrameInfo frame = await codec.getNextFrame();
+    codec.dispose();
     final int codecHeight = frame.image.height;
     final int codecWidth = frame.image.width;
     expect(codecHeight, 10);
@@ -55,6 +59,7 @@ void main() {
     final Uint8List bytes = await readFile('2x2.png');
     final Codec codec = await instantiateImageCodec(bytes, targetWidth: 10, allowUpscaling: false);
     final FrameInfo frame = await codec.getNextFrame();
+    codec.dispose();
     final int codecHeight = frame.image.height;
     final int codecWidth = frame.image.width;
     expect(codecHeight, 2);
@@ -65,6 +70,7 @@ void main() {
     final Uint8List bytes = await readFile('2x2.png');
     final Codec codec = await instantiateImageCodec(bytes, targetWidth: 10, targetHeight: 1);
     final FrameInfo frame = await codec.getNextFrame();
+    codec.dispose();
     final int codecHeight = frame.image.height;
     final int codecWidth = frame.image.width;
     expect(codecHeight, 1);
@@ -80,6 +86,7 @@ void main() {
       allowUpscaling: false,
     );
     final FrameInfo frame = await codec.getNextFrame();
+    codec.dispose();
     final int codecHeight = frame.image.height;
     final int codecWidth = frame.image.width;
     expect(codecHeight, 1);