Repository: flutter
Issue: [WebView] after some interaction it gets freezed and does not show errors or debug logs on iOS 
Labels: platform-ios,c: performance,p: webview,package,e: OS-version specific,P2,team-ios,triaged-ios

I load this url https://my.matterport.com/show/?m=383WDThzmTN&brand=0 inside of and it loads but when I click some buttons in the bottom of it (check the screenshot) it stops responding and stays like blocked.

![image](https://user-images.githubusercontent.com/76348/98364617-1b4bb500-1fff-11eb-8f9e-8d9f927a00e2.png)

It works fine on android but on iOS I have this problem.

I have it defined like:

```dart
WebView(
	debuggingEnabled: true,
	initialUrl: 'https://my.matterport.com/show/?m=383WDThzmTN&brand=0',
	javascriptMode: JavascriptMode.unrestricted,
	onPageFinished: (value) { print('WebView Loaded'); },
	onWebResourceError: (error) { print('Error on WebView'); },
)
```

But it does not print any error neither or see any logs from `debuggingEnabled`, also I do see logs running on android but not on iOS.

On the changelog I see this for `webview_flutter: 1.0.6`, which is the one I use, so it seems like something is happening.

```bash
Invoke the WebView.onWebResourceError on iOS when the webview content process crashes.
```


# Dependencies
- webview_flutter: 1.0.6
- Device with issue: Iphone SE 2020
- iOS < 14.

- flutter doctor:
```bash
$ flutter doctor -v
[✓] Flutter (Channel stable, 1.22.3, on Mac OS X 10.15.7 19H2, locale en-CO)
    • Flutter version 1.22.3 at /Users/danielgomez/projects/dev/flutter
    • Framework revision 8874f21e79 (8 days ago), 2020-10-29 14:14:35 -0700
    • Engine revision a1440ca392
    • Dart version 2.10.3

[!] Android toolchain - develop for Android devices (Android SDK version 30.0.2)
    • Android SDK at /Users/danielgomez/Library/Android/sdk
    • Platform android-30, build-tools 30.0.2
    • ANDROID_HOME = /Users/danielgomez/Library/Android/sdk
    • Java binary at: /Applications/Android Studio.app/Contents/jre/jdk/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b3-6222593)
    ✗ Android license status unknown.
      Run `flutter doctor --android-licenses` to accept the SDK licenses.
      See https://flutter.dev/docs/get-started/install/macos#android-setup for more details.

[✓] Xcode - develop for iOS and macOS (Xcode 12.0.1)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Xcode 12.0.1, Build version 12A7300
    • CocoaPods version 1.10.0

[!] Android Studio (version 4.1)
    • Android Studio at /Applications/Android Studio.app/Contents
    ✗ Flutter plugin not installed; this adds Flutter specific functionality.
    ✗ Dart plugin not installed; this adds Dart specific functionality.
    • Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b3-6222593)

[!] Android Studio (version 4.0)
    • Android Studio at /Applications/Android Studio 2.app/Contents
    ✗ Flutter plugin not installed; this adds Flutter specific functionality.
    ✗ Dart plugin not installed; this adds Dart specific functionality.
    • Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b3-6222593)

[✓] IntelliJ IDEA Community Edition (version 2020.2.2)
    • IntelliJ at /Applications/IntelliJ IDEA CE.app
    • Flutter plugin installed
    • Dart plugin version 202.8070

[!] VS Code (version 1.49.2)
    • VS Code at /Applications/Visual Studio Code.app/Contents
    ✗ Flutter extension not installed; install from
      https://marketplace.visualstudio.com/items?itemName=Dart-Code.flutter
```