Override ToString on more UIX classes

UIX.RenderApi/Microsoft/Iris/Render/Graphics/Image.cs

@@ -270,5 +270,7 @@ namespace Microsoft.Iris.Render.Graphics
         }
 
         internal delegate void ContentReloadedHandler(Image image);
+
+        public override string ToString() => $"{{Image {Identifier} {Format} {Size}}}";
     }
 }

UIX.RenderApi/Microsoft/Iris/Render/Size.cs

@@ -73,7 +73,7 @@ namespace Microsoft.Iris.Render
 
         public override int GetHashCode() => this.Width ^ this.Height;
 
-        public override string ToString() => base.ToString();
+        public override string ToString() => $"({Width} x {Height})";
 
         public Point ToPoint() => new Point(this.Width, this.Height);