title: BindableBase.SetProperty is not updating UI
body: <p>It is really weird, but UI is not updated when I call <code>BindableBase.SetProperty()</code>:</p>
  
  <pre><code>private string person;
  public string Person
  {
      get { return person; }
      set
      {
          person = value;
          SetProperty(ref this.person, value);//Not updating UI
          //OnPropertyChanged("Person");//It works really nice
      }
  }
  </code></pre>
  
  <p>I am using <code>Prism.Core.6.1.0\lib\net45\Prism.dll</code> and its <code>Version=6.1.0.0</code>.</p>
  
  <p>However, <code>OnPropertyChanged(string propertyName)</code> perfectly works:</p>
  
  <pre><code>public event PropertyChangedEventHandler PropertyChanged;
  public void OnPropertyChanged(string propertyName)
  {
      PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
  }
  </code></pre>
  
  <p>What I am missing? Any help would be greatly appreciated!:)</p>