Check for negative height or width before changing object since it will cause an exception

src/AddIns/DisplayBindings/WpfDesign/WpfDesign.Designer/Project/DesignPanel.cs

@@ -394,10 +394,12 @@ namespace ICSharpCode.WpfDesign.Designer
 					}
 					else
 					{
-						info.Bounds = new Rect(info.OriginalBounds.Left,
+						if (info.OriginalBounds.Width + dx >= 0 && info.OriginalBounds.Height + dy >= 0)  {
-							info.OriginalBounds.Top,
+							info.Bounds = new Rect(info.OriginalBounds.Left,
-							info.OriginalBounds.Width + dx,
+							                       info.OriginalBounds.Top,
-							info.OriginalBounds.Height + dy);
+							                       info.OriginalBounds.Width + dx,
+							                       info.OriginalBounds.Height + dy);
+						}
 					}
 					
 					placementOp.CurrentContainerBehavior.SetPosition(info);