[Webview] Headers on android webview are not shared to redirected page when using NavigationDelegate

### Steps to reproduce

1. Run app
2. See the 'Issue' page

### Expected results

On Android : Issue page should work without any tricks.

### Actual results

On Android : Issue page can't be loaded because NavigationDelegate.onNavigationRequest has been set and so headers are not persisted when the url is redirect to an other one of the same domain.

### Code sample

```yaml
webview_flutter: 4.13.0
webview_flutter_android: 4.7.0
webview_flutter_wkwebview: 3.22.0
```

Code sample

```dart
import 'dart:async';

import 'package:flutter/foundation.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: Home()));
}

class Home extends StatefulWidget {
const Home({super.key});

@override
State createState() => _HomeState();
}

class _HomeState extends State {
int index = 0;

@override
Widget build(final BuildContext context) {
return Scaffold(
body: IndexedStack(
index: index,
children: [
const CustomWebview(
url: 'https://httpbin.org/redirect-to?url=/bearer',
enableNavigationDelegate: true,
),
const CustomWebview(
url: 'https://httpbin.org/redirect-to?url=/bearer',
enableNavigationDelegate: false,
),
],
),
bottomNavigationBar: NavigationBar(
selectedIndex: index,
onDestinationSelected:
(final int selected) => setState(() => index = selected),
destinations: [
const NavigationDestination(
label: 'Issue',
icon: Icon(Icons.close, color: Colors.red),
),
const NavigationDestination(
label: 'No issue',
icon: Icon(Icons.check, color: Colors.green),
),
],
),
);
}
}

class CustomWebview extends StatefulWidget {
const CustomWebview({
super.key,
required this.url,
required this.enableNavigationDelegate,
});

final String url;
final bool enableNavigationDelegate;

@override
State createState() => _CustomWebview();
}

class _CustomWebview extends State {
late final WebViewController _controller;
bool loading = false;

@override
void initState() {
final PlatformWebViewControllerCreationParams params;
if (WebViewPlatform.instance is WebKitWebViewPlatform) {
params = WebKitWebViewControllerCreationParams(
allowsInlineMediaPlayback: true,
mediaTypesRequiringUserAction: PlaybackMediaTypes.values.toSet(),
);
} else if (WebViewPlatform.instance is AndroidWebViewPlatform) {
params = AndroidWebViewControllerCreationParams();
} else {
params = const PlatformWebViewControllerCreationParams();
}

final WebViewController controller =
WebViewController.fromPlatformCreationParams(params);

controller
..clearCache()
..setJavaScriptMode(JavaScriptMode.unrestricted)
..setBackgroundColor(Colors.white)
..setOverScrollMode(WebViewOverScrollMode.never)
..enableZoom(false);

if (widget.enableNavigationDelegate) {
controller.setNavigationDelegate(
NavigationDelegate(
onNavigationRequest: _onNavigationRequest,
onProgress: (final int value) {
setState(() => loading = value < 100);
},
onHttpError: (final HttpResponseError error) {
print("${error.request?.uri} ${error.response?.statusCode}");
},
),
);
}

if (controller.platform is WebKitWebViewController) {
} else if (controller.platform is AndroidWebViewController) {
AndroidWebViewController.enableDebugging(kDebugMode);
(controller.platform as AndroidWebViewController)
.setMediaPlaybackRequiresUserGesture(true);
}

controller.loadRequest(
Uri.parse(widget.url),
headers: {'Authorization': 'Bearer 12345'},
);

_controller = controller;

super.initState();
}

FutureOr _onNavigationRequest(
final NavigationRequest request,
) async {
if (kDebugMode) print(request.url);
return NavigationDecision.navigate;
}

@override
Widget build(final BuildContext context) {
late final Widget webViewWidget;
if (WebViewPlatform.instance is AndroidWebViewPlatform) {
webViewWidget = WebViewWidget.fromPlatformCreationParams(
params: AndroidWebViewWidgetCreationParams(
controller: _controller.platform,
displayWithHybridComposition: true,
),
);
} else {
webViewWidget = WebViewWidget(controller: _controller);
}

return GestureDetector(
onTap: () => FocusScope.of(context).unfocus(),
child: Scaffold(
appBar: AppBar(
title: const Text("Header issue"),
actions: [
IconButton(
onPressed: () {
_controller.reload();
},
icon: const Icon(Icons.refresh),
),
],
),
backgroundColor: Colors.white,
body: SafeArea(
child: Stack(
children: [
webViewWidget,
if (loading) const Center(child: CircularProgressIndicator()),
],
),
),
),
);
}
}

```

### Screenshots or Video

Screenshots / Video demonstration

| | |
| --- | --- |
|  |  |

### Logs

Logs

```console
Performing hot restart...
Syncing files to device sdk gphone64 x86 64...
Restarted application in 1 427ms.
D/EGL_emulation( 4633): app_time_stats: avg=6004.60ms min=21.84ms max=53675.92ms count=9
E/libEGL ( 4633): called unimplemented OpenGL ES API
D/EGL_emulation( 4633): app_time_stats: avg=6283.95ms min=55.17ms max=55815.22ms count=9
I/PlatformViewsController( 4633): Using hybrid composition for platform view: 0
I/PlatformViewsController( 4633): Using hybrid composition for platform view: 1
D/EGL_emulation( 4633): app_time_stats: avg=1421.17ms min=1421.17ms max=1421.17ms count=1
D/EGL_emulation( 4633): app_time_stats: avg=6307.30ms min=55.27ms max=56021.62ms count=9
I/flutter ( 4633): https://httpbin.org/bearer
I/tal.generations( 4633): NativeAlloc concurrent mark compact GC freed 842KB AllocSpace bytes, 2(32KB) LOS objects, 49% free, 7330KB/14MB, paused 735us,9.208ms total 40.763ms
I/flutter ( 4633): https://httpbin.org/bearer 401
E/libEGL ( 4633): called unimplemented OpenGL ES API
D/EGL_emulation( 4633): app_time_stats: avg=118.36ms min=28.05ms max=345.47ms count=11

```

### Flutter Doctor output

Doctor output

```console
[√] Flutter (Channel stable, 3.32.0, on Microsoft Windows [version 10.0.22631.5039], locale fr-FR) [590ms]
• Flutter version 3.32.0 on channel stable at C:\Users\engue\fvm\versions\3.32.0
• Upstream repository https://github.com/flutter/flutter.git
• Framework revision be698c48a6 (9 days ago), 2025-05-19 12:59:14 -0700
• Engine revision 1881800949
• Dart version 3.8.0
• DevTools version 2.45.1

[√] Windows Version (11 Professionnel 64-bit, 23H2, 2009) [6,5s]

[√] Android toolchain - develop for Android devices (Android SDK version 35.0.0) [2,8s]
• Android SDK at D:\Android
• Platform android-35, build-tools 35.0.0
• Java binary at: C:\Users\engue\.jdks\corretto-17.0.13\bin\java
This JDK is specified in your Flutter configuration.
To change the current JDK, run: `flutter config --jdk-dir="path/to/jdk"`.
• Java version OpenJDK Runtime Environment Corretto-17.0.13.11.1 (build 17.0.13+11-LTS)
• All Android licenses accepted.

[√] Chrome - develop for the web [217ms]
• Chrome at C:\Program Files (x86)\Google\Chrome\Application\chrome.exe

[√] Visual Studio - develop Windows apps (Visual Studio Community 2019 16.11.45) [216ms]
• Visual Studio at D:\dev
• Visual Studio Community 2019 version 16.11.35826.135
• Windows 10 SDK version 10.0.22621.0

[√] Android Studio (version 2024.3.2) [144ms]
• Android Studio at C:\Users\engue\AppData\Local\Programs\Android Studio
• Flutter plugin can be installed from:
https://plugins.jetbrains.com/plugin/9212-flutter
• Dart plugin can be installed from:
https://plugins.jetbrains.com/plugin/6351-dart
• Java version OpenJDK Runtime Environment (build 21.0.6+-13368085-b895.109)

[√] IntelliJ IDEA Ultimate Edition (version 2025.1) [142ms]
• IntelliJ at C:\Users\engue\AppData\Local\Programs\IntelliJ IDEA Ultimate
• Flutter plugin version 85.3.2
• Dart plugin version 251.25410.28

[√] Connected device (4 available) [428ms]
• sdk gphone64 x86 64 (mobile) • emulator-5554 • android-x64 • Android 15 (API 35) (emulator)
• Windows (desktop) • windows • windows-x64 • Microsoft Windows [version 10.0.22631.5039]
• Chrome (web) • chrome • web-javascript • Google Chrome 136.0.7103.114
• Edge (web) • edge • web-javascript • Microsoft Edge 135.0.3179.98

[√] Network resources [387ms]
• All expected network resources are available.

• No issues found!
```