/// <summary>
 /// Applies a style to the element.
 /// </summary>
 /// <param name="style">The style which is being applied.</param>
 /// <param name="selector">The selector which caused the style to be applied.</param>
 /// <param name="navigationExpression">The navigation expression associated with the style.</param>
 /// <param name="dprop">A <see cref="DependencyProperty"/> that identifies the dependency property which is being styled.</param>
 protected internal virtual void ApplyStyle(UvssRule style, UvssSelector selector, NavigationExpression?navigationExpression, DependencyProperty dprop)
 {
     if (dprop != null)
     {
         dprop.ApplyStyle(this, style);
     }
 }