lokdialog: Invalidate upon window size change

This problem can be seen with some of the dialogs like chart dialogs
where not all of the area which should be invalidated is invalidated.
The reason being that their container gets resized but not
lok-invalidated.

Change-Id: I12eb68e8644ca67b2666badb7b772b92a145c624
(cherry picked from commit 73fa910577ec99cf6331123d2fedffa5687b7e6f)
Reviewed-on: https://gerrit.libreoffice.org/51265Reviewed-by: Jan Holesovsky <kendy@collabora.com>
Tested-by: Jan Holesovsky <kendy@collabora.com>

vcl/source/window/window2.cxx

@@ -1396,6 +1396,12 @@ void Window::queue_resize(StateChangedType eReason)
         if (pBorderWindow)
             pBorderWindow->Resize();
     }
+
+    if (VclPtr<vcl::Window> pParent = GetParentWithLOKNotifier())
+    {
+        if (GetParentDialog())
+            LogicInvalidate(nullptr);
+    }
 }
 
 namespace