`RenderRepaintBoundary#toImage` works on Android/iOS, not Web

ErrorReport.md

ErrorReport

Target Platform: Web

Target OS version/browser: Chrome

Devices: Chrome

RenderRepaintBoundary#toImage works on Android/iOS, not Web

flutter/flutter#47721

ErrorReport:Flutter-Web:RenderRepaintBoundary.md

ErrorReport

Target Platform: Web

Target OS version/browser: Chrome

Devices: Chrome

RenderRepaintBoundary#toImage works on Android/iOS, not Web

main.dart

import 'dart:ui' as ui;

import 'package:flutter/material.dart';
import 'package:flutter/rendering.dart';

void main() => runApp(MyApp());

final _boundaryKey = GlobalKey();

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final title = 'Horizontal List';

    return MaterialApp(
      title: title,
      home: Scaffold(
        appBar: AppBar(
          title: Text(title),
        ),
        body: Center(
          child: RepaintBoundary(
            key: _boundaryKey,
            child: Container(
              width: 200,
              height: 100,
              color: Colors.green,
            ),
          ),
        ),
        floatingActionButton: FloatingActionButton(
          child: Text('Test'),
          onPressed: () async {
            RenderRepaintBoundary b = _boundaryKey.currentContext.findRenderObject();
            print('RenderRepaintBoundary $b');
            var image = await b.toImage(pixelRatio: ui.window.devicePixelRatio);
            var byteData = await image.toByteData();
            print('byteData.lengthInBytes ${byteData.lengthInBytes}');
          },
        ),
      ),
    );
  }
}