Uncaught SyntaxError: Failed to set the 'href' property on 'Location'

We have a webpage that does a redirect with js. It works fine on ios, but we are getting this error when trying it on android:

```
Uncaught SyntaxError: Failed to set the 'href' property on 'Location'
```

This is causing the flutterWebViewPlugin.onStateChanged.listen listener to stop firing.

The js line that does the redirect looks like this:

```
window.location = e.data.url + (e.data.url.indexOf('?') == -1 ? '?' : '&') + (params || {});
```

The location value is:
```
?notifyApp=success&SiteCode=SPA-SPA-006&TransactionId=73143e1d-e64b-44d1-9a6f-23d35a92618c&TransactionReference=044ZVxHUJ1vBfVGtf8B2opaqiuV8qu0d&Amount=25.00&Status=Complete&Optional1=&Optional2=&Optional3=&Optional4=&Optional5=&CurrencyCode=ZAR&IsTest=True&StatusMessage=Test%20transaction%20completed&Hash=19e304e53f23d5c6b4329af9757e4ede0457b5f573bd8a17bf01eeb01ef283fd1129dc670ec8508b17ac6f579f2fbde0311f0928a670c42c8a161a621d6d5640'
```