title: Ionic 4 doesn't hide the keyboard after submit
body: <p>I migrated my Ionic 3 app to Ionic 4. The problem is when I press the go button on the keyboard it doesn't close it. This is my code on the front-end: </p>
  
  <pre><code>    &lt;ion-header&gt;
    &lt;ion-toolbar color="primary"&gt;
      &lt;ion-buttons slot="start"&gt;
        &lt;ion-menu-button&gt;&lt;/ion-menu-button&gt;
      &lt;/ion-buttons&gt;
      &lt;ion-title&gt;2 variables&lt;/ion-title&gt;
    &lt;/ion-toolbar&gt;
  &lt;/ion-header&gt;
  &lt;ion-content color="secondary" padding&gt;
    &lt;form (ngSubmit)="calculateTwo(value1, value2)"&gt;
      &lt;ion-grid&gt;
        &lt;ion-row&gt;
          &lt;ion-col&gt;
            &lt;ion-item&gt;
              &lt;ion-label position="floating"&gt;value 1&lt;/ion-label&gt;
              &lt;ion-input name="value1" type="number" [(ngModel)]="value1"&gt;&lt;/ion-input&gt;
            &lt;/ion-item&gt;
          &lt;/ion-col&gt;
        &lt;/ion-row&gt;
        &lt;ion-row&gt;
          &lt;ion-col&gt;
            &lt;ion-item&gt;
              &lt;ion-label position="floating"&gt;Value 2&lt;/ion-label&gt;
              &lt;ion-input name="value2" type="number" [(ngModel)]="value2"&gt;&lt;/ion-input&gt;
            &lt;/ion-item&gt;
          &lt;/ion-col&gt;
        &lt;/ion-row&gt;
      &lt;/ion-grid&gt;
      &lt;ion-button shape="round" expand="full" type="submit"&gt;calculate&lt;/ion-button&gt;
    &lt;/form&gt;
    &lt;ion-card class="resultcard"&gt;
      &lt;ion-card-header class="headercolor"&gt;
        Result
      &lt;/ion-card-header&gt;
      &lt;ion-card-content&gt;
        {{result}}
      &lt;/ion-card-content&gt;
    &lt;/ion-card&gt;
  &lt;/ion-content&gt;
  </code></pre>
  
  <p>And this is my typescript file:</p>
  
  <pre><code> calculateTwo(value1, value2) {
      this.result = "Result: " + (value1 * value2);
      this.keyboard.hide();
    }
  </code></pre>
  
  <p>I am testing it on my phone (Sony z2). I can move to the next input field but when I press GO it doesn't trigger the <code>calculateTwo</code> function. Also the keyboard doesn't hide. </p>
  
  <p>This is my package.json file:</p>
  
  <pre><code>"dependencies": {
      "@angular/common": "^7.2.2",
      "@angular/core": "^7.2.2",
      "@angular/forms": "^7.2.2",
      "@angular/http": "^7.2.2",
      "@angular/platform-browser": "^7.2.2",
      "@angular/platform-browser-dynamic": "^7.2.2",
      "@angular/router": "^7.2.2",
      "@ionic-native/admob-free": "^5.4.0",
      "@ionic-native/core": "^5.0.0",
      "@ionic-native/keyboard": "^5.4.0",
      "@ionic-native/splash-screen": "^5.0.0",
      "@ionic-native/status-bar": "^5.0.0",
      "@ionic/angular": "^4.1.0",
      "cordova-admob-sdk": "0.24.1",
      "cordova-android": "^8.0.0",
      "cordova-plugin-admob-free": "0.26.0",
      "cordova-plugin-ionic-keyboard": "2.1.3",
      "cordova-promise-polyfill": "0.0.2",
      "core-js": "^2.5.4",
      "rxjs": "~6.3.3",
      "zone.js": "~0.8.29"
    },
    "devDependencies": {
      "@angular-devkit/architect": "~0.12.3",
      "@angular-devkit/build-angular": "~0.13.0",
      "@angular-devkit/core": "~7.2.3",
      "@angular-devkit/schematics": "~7.2.3",
      "@angular/cli": "~7.3.1",
      "@angular/compiler": "~7.2.2",
      "@angular/compiler-cli": "~7.2.2",
      "@angular/language-service": "~7.2.2",
      "@ionic/angular-toolkit": "~1.4.0",
      "@types/jasmine": "~2.8.8",
      "@types/jasminewd2": "~2.0.3",
      "@types/node": "~10.14.2",
      "codelyzer": "~4.5.0",
      "cordova-plugin-device": "^2.0.2",
      "cordova-plugin-ionic-webview": "^3.1.2",
      "cordova-plugin-splashscreen": "^5.0.2",
      "cordova-plugin-statusbar": "^2.4.2",
      "cordova-plugin-whitelist": "^1.3.3",
      "jasmine-core": "~2.99.1",
      "jasmine-spec-reporter": "~4.2.1",
      "karma": "^4.1.0",
      "karma-chrome-launcher": "~2.2.0",
      "karma-coverage-istanbul-reporter": "~2.0.1",
      "karma-jasmine": "~1.1.2",
      "karma-jasmine-html-reporter": "^0.2.2",
      "protractor": "~5.4.0",
      "ts-node": "~8.0.0",
      "tslint": "~5.12.0",
      "typescript": "~3.1.6"
    },
  </code></pre>
  
  <p>In my ionic 3 app this was working good. </p>
  
  <p>Can someone point me in the right direction? </p>