title: Angular form validation working only after focus change
body: <p>I have a angular form on which I want to do some validation. Now, when the textarea is loaded for the first time and I type something violating the validation, it does not show me error. </p>
  
  <p>When I change focus to some other element, then the error is shown. </p>
  
  <p>But, after that whenever there is a violation, the error is shown immediately whithout focus change required.</p>
  
  <pre><code>&lt;form [formGroup]="AddEditform" novalidate autocomplete="off"&gt;
      &lt;mat-form-field appearance="outline"&gt;
          &lt;textarea matInput name="user" formControlName="users" id="user"&gt;
          &lt;/textarea&gt;
          &lt;mat-error
              *ngIf="!AddEditform.valid &amp;&amp; AddEditform.get('users').hasError('maxlength')"
          &gt;
              Exceeded maximum length
          &lt;/mat-error&gt;
      &lt;/&lt;mat-form-field&gt;
  &lt;/form&gt;
  
  
  AddEditform: FormGroup;
  
  constructor(
    private fb: FormBuilder,
  ) { }
  
  ngOnInit() {
  
    this.AddEditform = this.fb.group({
      users: [
        '',
        [
          Validators.maxLength(100)
        ],
      ],
    });
  }
  </code></pre>
  
  <p>Why is this behavior happening? Why on the first time itself, the validation is not happening without focus change required?</p>