Support built-in disabling mechanism for reactive form controls instead of applying disabled attribute

[fateeand]

It looks like you're using the disabled attribute with a reactive form directive. If you set disabled to true
  when you set up this control in your component class, the disabled attribute will actually be set in the DOM for
  you. We recommend using this approach to avoid 'changed after checked' errors.

  Example:
  // Specify the `disabled` property at control creation time:
  form = new FormGroup({
    first: new FormControl({value: 'Nancy', disabled: true}, Validators.required),
    last: new FormControl('Drew', Validators.required)
  });

  // Controls can also be enabled/disabled after creation:
  form.get('first')?.enable();
  form.get('last')?.disable();