Keyboard apears and increases additional Viewport-Height

# Bug Report

## Problem
Keyboard apears and increases additional Viewport-Height

### What is expected to happen?

Viewport Height shoult be the same, on iOS if Keyboard apears.

### What does actually happen?

## Information

### Command or Code

```js
window.outerHeight
```

### Environment, Platform, Device
iPhone 8, 11 Emulator

### Version information
iOS: 13.2.2 Emulator
XCode: 11.2.1
cordova-ios: 5.0.1
cordova-lib: 9.01

no Dependencies,
only Cordova Boilerplatte

## Checklist

- [x] I searched for existing GitHub issues
- [x] I updated all Cordova tooling to most recent version
- [x] I included all the necessary information above

Reproduce the issue with window.outerHeight on an iPhone 8 or the iOS 13.2.2 emulator running cordova-ios 5.0.1, comparing the values before and after the keyboard appears. The payload names no source file or test, so start by tracing Cordova iOS viewport handling; done means the viewport height remains unchanged when the keyboard appears, as expected on iOS.

Written by the indexing model from the issue text.