[Controls]Use propotional values on test 1914 (#4434)

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Issue1914.cs

@@ -18,7 +18,7 @@ namespace Xamarin.Forms.Controls.Issues
 			public Rotator()
 			{
 				var image = new Image { Aspect = Aspect.AspectFit, Source = "bank.png" };
-				Children.Add (image, new Rectangle (.5,0,100,100), AbsoluteLayoutFlags.All);
+				Children.Add(image, new Rectangle(.5, .5, .5, .5), AbsoluteLayoutFlags.All);
 				VerticalOptions = HorizontalOptions = LayoutOptions.Center;
 				image.RotateTo(3600, 10000);
 			}