[web] Avoid using js_util.{jsify,dartify}() in dart2wasm for conver…

…ting to JS wrappers

The `js_util.jsify()` related code shows up in CPU profile of wonderous.

=> Any `SkwasmObjectWrapper` object invokes this logic in the
constructor and dispose method.

This PR

* makes `DomFinalizationRegistryExtension` accept JSAny types instead of
  Dart types and internally converting
  => Callsites can call more precise `<>.toJS*` extension methods
  => Avoids extra type checks on the objects

* avoids making `toJSAnyShallow` delegate to `toJSAnyDeep` in wasm
  => `toJSAnyDeep` uses `js_util.jsify()` which is slow
  => We cannot use `Object.toJSBox` due to it being slower to create JS
  boxes as it semantically does something different atm (see issue below)
  => Instead use conditional import of `dart:_wasm` which provides the
  necessary primitives
  => Similar for going from JS to Dart.

* Avoid calling converting from Dart object to JSAny more than needed
  (we did the operation twice for each registration and once for
  unregistration)

Issue dart-lang/sdk#55183

change condition

move

lib/web_ui/lib/src/engine/canvaskit/native_memory.dart

@@ -34,7 +34,7 @@ NativeMemoryFinalizationRegistry nativeMemoryFinalizationRegistry = NativeMemory
 class NativeMemoryFinalizationRegistry {
   void register(Object owner, UniqueRef<Object> ref) {
     if (browserSupportsFinalizationRegistry) {
-      _finalizationRegistry.register(owner, ref.toJSBox);
+      _finalizationRegistry.register(owner.toJSAnyShallow, ref.toJSBox);
     }
   }
 }

lib/web_ui/lib/src/engine/dom.dart

@@ -7,6 +7,7 @@ import 'dart:js_interop';
 import 'dart:math' as math;
 import 'dart:typed_data';
 
+import 'package:ui/src/engine/skwasm/skwasm_stub.dart' if (dart.library.ffi) 'package:ui/src/engine/skwasm/skwasm_impl.dart';
 import 'package:js/js_util.dart' as js_util;
 import 'package:meta/meta.dart';
 
@@ -36,27 +37,27 @@ import 'browser_detection.dart';
 /// are currently represented across web backends, these extensions should be
 /// used carefully and only on types that are known to not contains `JSNull` and
 /// `JSUndefined`.
-extension ObjectToJSAnyExtension on Object {
-  JSAny get toJSAnyShallow {
-    if (isWasm) {
-      return toJSAnyDeep;
-    } else {
-      return this as JSAny;
-    }
-  }
 
+extension ObjectToJSAnyExtension on Object {
+  // Once `Object.toJSBox` is faster (see
+  // https://github.com/dart-lang/sdk/issues/55183) we can remove this
+  // backend-specific workaround.
+  @pragma('wasm:prefer-inline')
+  @pragma('dart2js:tryInline')
+  JSAny get toJSAnyShallow => dartToJsWrapper(this);
+
+  @pragma('wasm:prefer-inline')
+  @pragma('dart2js:tryInline')
   JSAny get toJSAnyDeep => js_util.jsify(this) as JSAny;
 }
 
 extension JSAnyToObjectExtension on JSAny {
-  Object get toObjectShallow {
-    if (isWasm) {
-      return toObjectDeep;
-    } else {
-      return this;
-    }
-  }
+  @pragma('wasm:prefer-inline')
+  @pragma('dart2js:tryInline')
+  Object get toObjectShallow => jsWrapperToDart(this);
 
+  @pragma('wasm:prefer-inline')
+  @pragma('dart2js:tryInline')
   Object get toObjectDeep => js_util.dartify(this)!;
 }
 
@@ -3662,22 +3663,13 @@ DomFinalizationRegistry createDomFinalizationRegistry(JSFunction cleanup) =>
 
 extension DomFinalizationRegistryExtension on DomFinalizationRegistry {
   @JS('register')
-  external JSVoid _register1(JSAny target, JSAny value);
+  external JSVoid register(JSAny target, JSAny value);
 
   @JS('register')
-  external JSVoid _register2(JSAny target, JSAny value, JSAny token);
-  void register(Object target, Object value, [Object? token]) {
-    if (token != null) {
-      _register2(
-          target.toJSAnyShallow, value.toJSAnyShallow, token.toJSAnyShallow);
-    } else {
-      _register1(target.toJSAnyShallow, value.toJSAnyShallow);
-    }
-  }
+  external JSVoid registerWithToken(JSAny target, JSAny value, JSAny token);
 
   @JS('unregister')
-  external JSVoid _unregister(JSAny token);
-  void unregister(Object token) => _unregister(token.toJSAnyShallow);
+  external JSVoid unregister(JSAny token);
 }
 
 /// Whether the current browser supports `FinalizationRegistry`.

lib/web_ui/lib/src/engine/skwasm/skwasm_impl.dart

@@ -11,6 +11,7 @@ import 'dart:ffi';
 
 export 'skwasm_impl/canvas.dart';
 export 'skwasm_impl/codecs.dart';
+export 'skwasm_impl/dart_js_conversion.dart';
 export 'skwasm_impl/filters.dart';
 export 'skwasm_impl/font_collection.dart';
 export 'skwasm_impl/image.dart';

lib/web_ui/lib/src/engine/skwasm/skwasm_impl/dart_js_conversion.dart

@@ -0,0 +1,16 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:_wasm';
+import 'dart:js_interop';
+
+@pragma('wasm:prefer-inline')
+@pragma('dart2js:tryInline')
+JSAny dartToJsWrapper(Object object) =>
+    WasmAnyRef.fromObject(object).externalize().toJS;
+
+@pragma('wasm:prefer-inline')
+@pragma('dart2js:tryInline')
+Object jsWrapperToDart(JSAny jsWrapper) =>
+    externRefForJSAny(jsWrapper).internalize()!.toObject();

lib/web_ui/lib/src/engine/skwasm/skwasm_impl/memory.dart

@@ -36,11 +36,14 @@ class SkwasmFinalizationRegistry<T extends NativeType> {
   final DisposeFunction<T> dispose;
 
   void register(SkwasmObjectWrapper<T> wrapper) {
-    registry.register(wrapper, wrapper.handle.address, wrapper);
+    final JSAny jsWrapper = wrapper.toJSAnyShallow;
+    registry.registerWithToken(
+        jsWrapper, wrapper.handle.address.toJS, jsWrapper);
   }
 
   void evict(SkwasmObjectWrapper<T> wrapper) {
-    registry.unregister(wrapper);
+    final JSAny jsWrapper = wrapper.toJSAnyShallow;
+    registry.unregister(jsWrapper);
     dispose(wrapper.handle);
   }
 }

lib/web_ui/lib/src/engine/skwasm/skwasm_stub.dart

@@ -6,4 +6,5 @@
 // ignore: unnecessary_library_directive
 library skwasm_stub;
 
+export 'skwasm_stub/dart_js_conversion.dart';
 export 'skwasm_stub/renderer.dart';

lib/web_ui/lib/src/engine/skwasm/skwasm_stub/dart_js_conversion.dart

@@ -0,0 +1,13 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:js_interop';
+
+@pragma('wasm:prefer-inline')
+@pragma('dart2js:tryInline')
+JSAny dartToJsWrapper(Object object) => object as JSAny;
+
+@pragma('wasm:prefer-inline')
+@pragma('dart2js:tryInline')
+Object jsWrapperToDart(JSAny jsWrapper) => jsWrapper;