flutter_webview 兼容问题

### 使用flutter_boost无法打开 webview_flutter: ^1.0.5

**Flutter Boost Version**
flutter_boost: ^1.17.1
**Target Platform:**
iOS
**Target OS version/browser:**
14.0.1
**Devices:**
iPhone xs

## Logs
add your crash log or something else.

```
[✓] Flutter (Channel stable, 1.22.2, on Mac OS X 10.15.5 19F101, locale
zh-Hans-CN)
⣟Unable to find any JVMs matching version "1.8".
[!] Android toolchain - develop for Android devices (Android SDK version 29.0.2)
✗ 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)
[!] Android Studio (not installed)
[✓] IntelliJ IDEA Ultimate Edition (version 2020.2.3)
[✓] VS Code (version 1.50.1)

[✓] Connected device (1 available)

! Doctor found issues in 2 categories.
```

Start by reproducing the failure with Flutter 1.22.2, flutter_boost 1.17.1, webview_flutter 1.0.5, iOS 14.0.1, and an iPhone XS. Capture the missing crash or error logs and verify whether the web view opens; done means the compatibility cause and a supported configuration are documented.

Written by the indexing model from the issue text.