Ionic Build for Production Breaks UI in iOS 11.3

**Ionic version:**
[ ] **2.x**
[x] **3.x**
[ ] **4.x**

**I'm submitting a ...**
[x] bug report
[ ] feature request

**Current behavior:**
Building the application for production breaks the UI interaction (inputs, buttons, forms elements, keyboard) in iOS 11.3.

**Expected behavior:**
Building for production should result in the application build working even more performant than in development.

**Steps to reproduce:**
Build the application for production with the --prod flag in an iOS 11.3 device.

**Related code:**

```javascript
ionic cordova run ios --prod --device
```
**Other information:**
I've already tested with different versions of the **app-scripts** module since I'm aware of the related reported issue [13718](https://github.com/ionic-team/ionic/issues/13718). So I also tested **uglify-es:3.2.2** version independently as a dev-dependency.

**Ionic info:**

```
@ionic/cli-utils : 1.19.2
ionic (Ionic CLI) : 3.20.0

global packages:

cordova (Cordova CLI) : 7.1.0 / 8.0.0 (tested with both versions)
local packages:

@ionic/app-scripts : 3.1.7 / 3.1.8 (tested with both versions)
Cordova Platforms : android 6.3.0 ios 4.5.4
Ionic Framework : ionic-angular 3.9.2
System:

Android SDK Tools : 26.1.1
ios-deploy : 1.9.2
ios-sim : 6.1.2
Node : v8.11.1
npm : 5.6.0
OS : macOS High Sierra
Xcode : Xcode 9.3 Build version 9E145
```

Start by reproducing `ionic cordova run ios --prod --device` on iOS 11.3 with the Ionic CLI, app-scripts, Cordova, and Ionic Framework versions listed in the report. Inspect the production-build path and its interaction with the iOS output; done means inputs, buttons, forms, and keyboard interaction work in the production build as they do in development.

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