Repository: flutter
Issue: [platform-view][android]loupe doesn't work properly
Labels: c: new feature,platform-android,a: platform-views,has reproducible steps,P3,found in release: 3.7,found in release: 3.9,team-android,triaged-android

The magnify glass (loupe) in android app is showing a grey box instead of magnified text. The app launched on web in android chrome browser is working perfectly.

Tested it on Android API 31. 
### **Expected Behaviour:**
Whenever, we select or move cursor on text, the magify glass should display the magnified text ( Added in Android P)
### **Current Behaviour:**
Gray shadow instead of magnified text as shown below:

[android_webview_magifier_loupe.webm](https://user-images.githubusercontent.com/57312080/222518508-03917bb8-5653-4235-9229-630e66a04f57.webm)

**### Steps to Reproduce:**

1. Add any url or html page to `webview_flutter` widget,
2. Run the Android app, select or move cursor over text to get magnifier

### `webview_flutter` & `webview_flutter_android` version
```
  webview_flutter: ^4.0.5
  webview_flutter_android: ^3.3.1
  webview_flutter_platform_interface: ^2.0.2
```
### Android  (build.gradle)
`minSdkVersion 20`
 `compileSdkVersion 33`

### Code Sample
The code sample is taken from the [example](https://pub.dev/packages/webview_flutter/example), removed additional functionalities to keep it simple.

<details>
  <summary>Code Sample</summary>
  

  ```dart
import 'package:flutter/material.dart';
import 'package:webview_flutter/webview_flutter.dart';
import 'package:webview_flutter_android/webview_flutter_android.dart';
import 'package:webview_flutter_wkwebview/webview_flutter_wkwebview.dart';


void main() => runApp(const MaterialApp(home: WebViewExample()));

class WebViewExample extends StatefulWidget {
  const WebViewExample({super.key});

  @override
  State<WebViewExample> createState() => _WebViewExampleState();
}

class _WebViewExampleState extends State<WebViewExample> {
  late final WebViewController _controller;

  @override
  void initState() {
    super.initState();
    // #docregion platform_features
    late final PlatformWebViewControllerCreationParams params;
    if (WebViewPlatform.instance is WebKitWebViewPlatform) {
      params = WebKitWebViewControllerCreationParams(
        allowsInlineMediaPlayback: true,
        mediaTypesRequiringUserAction: const <PlaybackMediaTypes>{},
      );
    } else {
      params = const PlatformWebViewControllerCreationParams();
    }

    final WebViewController controller =
    WebViewController.fromPlatformCreationParams(params);
    // #enddocregion platform_features
    controller
      ..setJavaScriptMode(JavaScriptMode.unrestricted)
      ..setBackgroundColor(const Color(0x00000000))
      ..addJavaScriptChannel(
        'Toaster',
        onMessageReceived: (JavaScriptMessage message) {
          ScaffoldMessenger.of(context).showSnackBar(
            SnackBar(content: Text(message.message)),
          );
        },
      )
      ..loadRequest(Uri.parse('https://flutter.dev'));

    // #docregion platform_features
    if (controller.platform is AndroidWebViewController) {
      AndroidWebViewController.enableDebugging(true);
      (controller.platform as AndroidWebViewController)
          .setMediaPlaybackRequiresUserGesture(false);
    }
    _controller = controller;
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.green,
      appBar: AppBar(
        title: const Text('Flutter WebView example'),
      ),
      body: WebViewWidget(controller: _controller),
    );
  }
}

  ```
</details>


### Flutter Doctor:
```
Doctor summary (to see all details, run flutter doctor -v):
[✓] Flutter (Channel stable, 3.7.3, on macOS 13.0 22A380 darwin-arm64, locale en-IN)
[✓] Android toolchain - develop for Android devices (Android SDK version 31.0.0)
[✓] Xcode - develop for iOS and macOS (Xcode 14.1)
[✓] Chrome - develop for the web
[!] Android Studio (version 2022.1)
    ✗ Unable to find bundled Java version.
[✓] IntelliJ IDEA Community Edition (version 2022.2.2)
[✓] VS Code (version 1.74.3)
[✓] Connected device (3 available)
[✓] HTTP Host Availability
```

PS:
Magnify feature is working fine on web app, tested on chrome browser in android
(expecting the same on Android App)

[web_magnifier_loupe.webm](https://user-images.githubusercontent.com/57312080/222519485-cf107cea-cb12-4b57-91de-9f7ccd1121ee.webm)

Thanks!