title: ionic:Change event is not fired on <ion-input> when the input value is changed from external script
body: <p>I want to call the function whenever the input is changed.</p>
  
  <p>I have created the following in my home.html file</p>
  
  <pre><code>&lt;ion-input type="text" class="scoreboardus" [(ngModel)]='text' 
        (input)='onInputTime($event.target.value)' (change)='onChangeTime($event.target.value)'&gt;
     &lt;/ion-input&gt;
  </code></pre>
  
  <p>and in home.ts file</p>
  
  <pre><code>onChangeTime() {
    alert('onChangeTime called');
  }
  
  onInputTime() {
    alert('onInputTime called');
  }
  </code></pre>
  
  <p>the above code works fine if manually give values in the input field.</p>
  
  <p>My problem:</p>
  
  <p>I am changing input value from one of external javascript file.</p>
  
  <pre><code>$('.scoreboardus input').val(200).trigger('onchange');
  </code></pre>
  
  <p>The above code change the input field value… But function is not called</p>
  
  <p>resultant code should work after creating an app.</p>