title: MaxLength on number not working
body: <blockquote>
    <p>i using angular 4.3.3</p>
  </blockquote>
  
  <p>maxlength 11 max span  message is not showing</p>
  
  <pre><code>&lt;input type="number" class="form-control" id="orderId"   [(ngModel)]="orderIdModel"  name="orderId" #orderId="ngModel" required  maxLength="11"  /&gt;
  &lt;div *ngIf="orderId.errors"&gt;
                      &lt;span *ngIf="orderId.errors.required"class="not-valid"&gt;required&lt;/span&gt;
                      &lt;span *ngIf="orderId.errors.maxlength"class="not-valid"&gt; 11 max&lt;/span&gt;
      &lt;/div&gt; 
  </code></pre>