class MainActivity: FlutterFragmentActivity() {

    override fun configureFlutterEngine(@NonNull flutterEngine: FlutterEngine) {
        GeneratedPluginRegistrant.registerWith(flutterEngine);
    }
}

 await binding.convertFlutterSurfaceToImage();

    // Trigger a frame.
    await tester.pumpAndSettle();
    await binding.takeScreenshot('screenshot-1');

 flutter drive --driver=test_driver/integration_test.dart --target=integration_test/home_test.dart

Failure in method: screenshot
══╡ EXCEPTION CAUGHT BY FLUTTER TEST FRAMEWORK ╞═════════════════
The following PlatformException was thrown running a test:
PlatformException(Could not copy the pixels, FlutterView is null,
null, null)

When the exception was thrown, this was the stack:
#0      StandardMethodCodec.decodeEnvelope (package:flutter/src/services/message_codecs.dart:607:7)
#1      MethodChannel._invokeMethod (package:flutter/src/services/platform_channel.dart:156:18)
<asynchronous suspension>
#2      IOCallbackManager.takeScreenshot (package:integration_test/_callback_io.dart:91:33)
<asynchronous suspension>
#3      IntegrationTestWidgetsFlutterBinding.takeScreenshot (package:integration_test/integration_test.dart:175:39)
<asynchronous suspension>
#4      main.<anonymous closure> (file:///home/tim/AndroidStudioProjects/untitled/integration_test/home_test.dart:40:5)
<asynchronous suspension>
#5      testWidgets.<anonymous closure>.<anonymous closure> (package:flutter_test/src/widget_tester.dart:176:15)
<asynchronous suspension>
#6      TestWidgetsFlutterBinding._runTestBody (package:flutter_test/src/binding.dart:817:5)
<asynchronous suspension>

flutter doctor
Doctor summary (to see all details, run flutter doctor -v):
[✓] Flutter (Channel stable, 2.5.0, on KDE neon User Edition 5.22 5.8.0-63-generic, locale en_NZ.UTF-8)
[✓] Android toolchain - develop for Android devices (Android SDK version 31.0.0)
[✓] Chrome - develop for the web
[✓] Android Studio (version 2020.3)
[✓] Android Studio
[✓] Connected device (3 available)

• No issues found!