Fixed SD2-387: Main Menu: Sub menu position wrong

git-svn-id: svn://svn.sharpdevelop.net/sharpdevelop/trunk@387 1ccf3a8d-04fe-1044-b7c0-cef0b8235c61

src/Main/Core/Project/Src/AddInTree/AddIn/DefaultDoozers/MenuItem/Gui/Menu.cs

@@ -53,7 +53,9 @@ namespace ICSharpCode.Core
 		}
 		protected override void OnDropDownShow(EventArgs e)
 		{
-			CreateDropDownItems();
+			if (!this.DropDown.Visible) {
+				CreateDropDownItems();
+			}
 			base.OnDropDownShow(e);
 		}