title: ERROR TypeError: Class constructor EventEmitter cannot be invoked without 'new' in Ionic 4
body: <p>In ionic 4, <code>ionic serve</code> completed successfully. When I open the application in the browser, I'm getting the below error and nothing is loading.</p>
  
  <pre><code>AppComponent_Host.ngfactory.js? [sm]:1 ERROR TypeError: Class constructor EventEmitter cannot be invoked without 'new'
      at new BackButtonEmitter (platform.js:17)
      at new Platform (platform.js:32)
      at _createClass (core.js:10354)
      at _createProviderInstance (core.js:10321)
      at resolveNgModuleDep (core.js:10266)
      at NgModuleRef_.get (core.js:11373)
      at resolveDep (core.js:11865)
      at createClass (core.js:11736)
      at createDirectiveInstance (core.js:11559)
      at createViewNodes (core.js:13100)
  </code></pre>
  
  <p>I referred <a href="https://stackoverflow.com/questions/36577683/babel-error-class-constructor-foo-cannot-be-invoked-without-new">Babel error: Class constructor Foo cannot be invoked without &#39;new&#39;</a> and it didn't help. </p>
  
  <p>Package.json looks like below.</p>
  
  <pre><code>  "name": "T.S.S",
    "version": "0.0.1",
    "author": "Ionic Framework",
    "homepage": "http://ionicframework.com/",
    "scripts": {
      "ng": "ng",
      "start": "ng serve",
      "build": "ng build",
      "test": "ng test",
      "lint": "ng lint",
      "e2e": "ng e2e"
    },
    "private": true,
    "dependencies": {
      "@angular/animations": "^6.1.9",
      "@angular/common": "~6.1.1",
      "@angular/core": "^6.1.9",
      "@angular/forms": "~6.1.1",
      "@angular/http": "~6.1.1",
      "@angular/platform-browser": "~6.1.1",
      "@angular/platform-browser-dynamic": "^6.1.3",
      "@angular/router": "~6.1.1",
      "@ctrl/ngx-chartjs": "^1.0.3",
      "@ionic-native/core": "5.0.0-beta.14",
      "@ionic-native/date-picker": "^4.15.0",
      "@ionic-native/ionic-webview": "^5.0.0-beta.17",
      "@ionic-native/splash-screen": "5.0.0-beta.14",
      "@ionic-native/status-bar": "5.0.0-beta.14",
      "@ionic/angular": "^4.0.0-beta.0",
      "angular-2-dropdown-multiselect": "^1.8.1",
      "chart.js": "^2.7.2",
      "cordova-android": "7.0.0",
      "cordova-browser": "5.0.4",
      "cordova-plugin-device": "^2.0.2",
      "cordova-plugin-ionic-keyboard": "^2.1.2",
      "cordova-plugin-ionic-webview": "^2.1.0",
      "cordova-plugin-splashscreen": "^5.0.2",
      "cordova-plugin-statusbar": "^2.4.2",
      "cordova-plugin-whitelist": "^1.3.3",
      "core-js": "^2.5.3",
      "install": "^0.12.1",
      "lodash": "^4.17.10",
      "ng2-datepicker": "^3.1.1",
      "ng4-loading-spinner": "^1.2.3",
      "ngx-owl-carousel": "^2.0.7",
      "rxjs": "6.2.2",
      "typescriptnpm": "^1.0.1",
      "web-animations-js": "^2.3.1",
      "zone.js": "^0.8.26"
    },
    "devDependencies": {
      "@angular-devkit/architect": "~0.7.2",
      "@angular-devkit/build-angular": "^0.7.5",
      "@angular-devkit/core": "~0.7.2",
      "@angular-devkit/schematics": "~0.7.2",
      "@angular/cli": "^6.1.5",
      "@angular/compiler": "^6.1.3",
      "@angular/compiler-cli": "^6.1.6",
      "@angular/language-service": "~6.1.1",
      "@ionic/ng-toolkit": "^1.0.0",
      "@ionic/schematics-angular": "^1.0.0",
      "@types/jasmine": "~2.8.6",
      "@types/jasminewd2": "~2.0.3",
      "@types/node": "~10.7.1",
      "codelyzer": "~4.4.2",
      "jasmine-core": "~2.99.1",
      "jasmine-spec-reporter": "~4.2.1",
      "karma": "~3.0.0",
      "karma-chrome-launcher": "~2.2.0",
      "karma-coverage-istanbul-reporter": "~2.0.0",
      "karma-jasmine": "~1.1.1",
      "karma-jasmine-html-reporter": "^0.2.2",
      "primeicons": "^1.0.0-beta.10",
      "primeng": "^6.1.2",
      "protractor": "~5.4.0",
      "ts-node": "~7.0.0",
      "tslint": "~5.11.0",
      "typescript": "^2.9.2"
    },
    "description": "An Ionic project",
    "cordova": {
      "plugins": {
        "cordova-plugin-whitelist": {},
        "cordova-plugin-device": {},
        "cordova-plugin-splashscreen": {},
        "cordova-plugin-ionic-keyboard": {},
        "cordova-plugin-statusbar": {},
        "cordova-plugin-ionic-webview": {}
      },
      "platforms": [
        "android",
        "browser"
      ]
    }
  }
  </code></pre>
  
  <p>Created an issue with Ionic as well. <a href="https://github.com/ionic-team/ionic/issues/15939" rel="nofollow noreferrer">https://github.com/ionic-team/ionic/issues/15939</a>.</p>
  
  <p>Any suggestions on making the application work?</p>